ICSE – Grade 8 – Chemistry – Ch 01 – QA

Questions & Answers

ICSE - Grade - 8

Subject: Chemistry

Chapter - 01 - Matter

Types of Questions

MCQ

  1. What is matter?
    A. Anything that has volume
    B. Anything that has mass
     C. Anything that occupies space and has mass
     D. Anything that is visible
     Answer: C

 

  1. Which of the following is NOT matter?
    A. Air
    B. Heat
     C. Water
     D. Iron
     Answer: B

 

  1. The force of attraction between particles is maximum in:
    A. Gases
    B. Liquids
     C. Solids
     D. Plasma
     Answer: C

 

  1. The state of matter with the least interparticle space is:
    A. Solid
    B. Liquid
     C. Gas
     D. Vapour
     Answer: A

 

  1. Which of these has the highest kinetic energy?
    A. Solid
    B. Liquid
     C. Gas
     D. Plasma
     Answer: C

 

  1. Matter resists applied force because:
    A. It is heavy
    B. It has volume
     C. It is made of particles
     D. It is rigid
     Answer: C

 

  1. Which of these can be compressed easily?
    A. Solids
    B. Liquids
     C. Gases
     D. All of the above
     Answer: C

 

  1. Interparticle space is maximum in:
    A. Solids
    B. Liquids
     C. Gases
     D. All equal
     Answer: C

 

  1. The process of conversion of gas into liquid is called:
    A. Boiling
    B. Evaporation
     C. Freezing
     D. Condensation
     Answer: D

 

  1. The boiling point of water is:
    A. 0°C
    B. 25°C
     C. 50°C
     D. 100°C
     Answer: D

 

  1. Which of the following is an example of sublimation?
    A. Water boiling
    B. Ice melting
     C. Camphor vaporising
     D. Milk freezing
     Answer: C

 

  1. Which of the following is not a state of matter?
    A. Solid
    B. Liquid
     C. Energy
     D. Gas
     Answer: C

 

  1. The melting point of ice is:
    A. 0°C
    B. 100°C
     C. –10°C
     D. 25°C
     Answer: A

 

  1. Which one flows and takes the shape of the container but has fixed volume?
    A. Solid
    B. Liquid
     C. Gas
     D. Plasma
     Answer: B

 

  1. On heating, a solid usually turns into a:
    A. Gas
    B. Liquid
     C. Plasma
     D. Solution
     Answer: B

 

  1. Gases are:
    A. Rigid and incompressible
    B. Compressible and flow freely
     C. Rigid and flow easily
     D. Incompressible and do not flow
     Answer: B

 

  1. Liquefaction means:
    A. Solid to gas
    B. Liquid to gas
     C. Gas to liquid
     D. Liquid to solid
     Answer: C

 

  1. Which process involves conversion of solid directly to gas?
    A. Fusion
    B. Boiling
     C. Sublimation
     D. Condensation
     Answer: C

 

  1. Which of the following is a physical change?
    A. Burning of paper
    B. Rusting of iron
     C. Melting of ice
     D. Cooking of food
     Answer: C

 

  1. According to Kinetic Theory, particles of matter:
    A. Are at rest
    B. Are stationary
     C. Move continuously
     D. Are fixed
     Answer: C

 

  1. The particles in gases are:
    A. Closely packed
    B. Loosely packed
     C. Widely spaced
     D. Packed tightly
     Answer: C

 

  1. Sublimation is shown by:
    A. Camphor
    B. Water
     C. Salt
     D. Sugar
     Answer: A

 

  1. On cooling, a gas changes to:
    A. Solid
    B. Liquid
     C. Plasma
     D. Vapour
     Answer: B

 

  1. Freezing point of water is:
    A. 25°C
    B. 0°C
     C. –5°C
     D. 100°C
     Answer: B

 

  1. Matter is made up of:
    A. Energy
    B. Light
     C. Particles
     D. Waves
     Answer: C

 

  1. Which of these is not compressible?
    A. Air
    B. Water
     C. Iron rod
     D. Steam
     Answer: C

 

  1. Interparticle forces in gases are:
    A. Very strong
    B. Moderate
     C. Weak or negligible
     D. Extremely strong
     Answer: C

 

  1. The process of changing liquid to solid is called:
    A. Melting
    B. Boiling
     C. Freezing
     D. Evaporation
     Answer: C

 

  1. Which of the following has no fixed shape or volume?
    A. Solid
    B. Liquid
     C. Gas
     D. Ice
     Answer: C

 

  1. Which factor causes interconversion of matter?
    A. Colour
    B. Shape
     C. Temperature and pressure
     D. Taste
     Answer: C

 

  1. The law which states mass can neither be created nor destroyed is:
    A. Law of Inertia
    B. Law of Conservation of Energy
     C. Law of Conservation of Mass
     D. Newton’s Third Law
     Answer: C

 

  1. Which instrument proves Law of Conservation of Mass?
    A. Burette
    B. Landolt’s apparatus
     C. Flask
     D. Beaker
     Answer: B

 

  1. Example of condensation is:
    A. Water boiling
    B. Iodine subliming
     C. Steam changing to water
     D. Water freezing
     Answer: C

 

  1. The kinetic energy of particles increases when:
    A. They are cooled
    B. Pressure is increased
     C. They are heated
     D. Volume is decreased
     Answer: C

 

  1. On heating, interparticle space:
    A. Increases
    B. Decreases
     C. Disappears
     D. Becomes zero
     Answer: A

 

  1. A rigid body with definite shape is a:
    A. Solid
    B. Liquid
     C. Gas
     D. Vapour
     Answer: A

 

  1. The temperature at which a substance boils is called:
    A. Freezing point
    B. Boiling point
     C. Melting point
     D. Condensation point
     Answer: B

 

  1. The conversion of water to water vapour is called:
    A. Condensation
    B. Evaporation
     C. Freezing
     D. Melting
     Answer: B

 

  1. Which of the following is a chemical change?
    A. Melting of ice
    B. Evaporation of water
     C. Burning of candle
     D. Condensation of steam
     Answer: C

 

  1. The melting point of a pure substance is:
    A. Variable
    B. Fixed
     C. Unknown
     D. Non-measurable
     Answer: B

 

  1. The process used to convert gas to solid directly is called:
    A. Fusion
    B. Deposition
     C. Evaporation
     D. Freezing
     Answer: B

 

  1. The particles of matter:
    A. Do not move
    B. Remain stationary
     C. Are in continuous motion
     D. Vibrate only in solids
     Answer: C

 

  1. The process of solid changing to gas without becoming liquid is:
    A. Boiling
    B. Sublimation
     C. Freezing
     D. Condensation
     Answer: B

 

  1. The process opposite to evaporation is:
    A. Freezing
    B. Condensation
     C. Melting
     D. Boiling
     Answer: B

 

  1. Which one has definite shape and volume?
    A. Gas
    B. Liquid
     C. Solid
     D. Vapour
     Answer: C

 

  1. Evaporation occurs at:
    A. Boiling point
    B. Room temperature only
     C. Surface of liquid at any temperature
     D. Freezing point
     Answer: C

 

  1. The particles of matter attract each other due to:
    A. Energy
    B. Gravitational pull
     C. Intermolecular force
     D. Magnetic force
     Answer: C

 

  1. Which state of matter has the strongest force of attraction?
    A. Gas
    B. Liquid
     C. Solid
     D. Vapour
     Answer: C

 

  1. The solid directly formed from gas is called:
    A. Vapour
    B. Liquid
     C. Condensate
     D. Sublimate
     Answer: D

 

  1. Water turning to ice is an example of:
    A. Freezing
    B. Melting
     C. Boiling
     D. Condensation
     Answer: A

Fill in the Blanks

  1. Anything that occupies space and has mass is called ______.
     Answer: Matter


  2. Matter is made up of tiny ______.
     Answer: Particles


  3. The force of attraction between particles is strongest in ______.
     Answer: Solids


  4. The force of attraction between particles is weakest in ______.
     Answer: Gases


  5. The state of matter with a definite shape and volume is ______.
     Answer: Solid


  6. The state of matter that has no fixed shape but fixed volume is ______.
     Answer: Liquid


  7. The state of matter that has neither fixed shape nor fixed volume is ______.
     Answer: Gas


  8. The interparticle space is maximum in ______.
     Answer: Gases


  9. The interparticle space is minimum in ______.
     Answer: Solids


  10. Particles of matter are in constant ______.
     Answer: Motion


  11. Matter resists applied force because it is made up of ______.
     Answer: Particles


  12. The kinetic energy of particles increases with ______.
     Answer: Temperature


  13. The process by which solid changes into liquid is called ______.
     Answer: Melting


  14. The fixed temperature at which a solid melts is called its ______.
     Answer: Melting point


  15. The process by which a liquid changes into gas is called ______.
     Answer: Evaporation


  16. The fixed temperature at which a liquid boils is called its ______.
     Answer: Boiling point


  17. The process by which gas changes into liquid is called ______.
     Answer: Condensation


  18. The temperature at which gas condenses is called ______.
     Answer: Condensation point


  19. The process of changing gas to liquid by cooling or applying pressure is called ______.
     Answer: Liquefaction


  20. The process by which liquid changes into solid is called ______.
     Answer: Freezing


  21. The fixed temperature at which a liquid freezes is called its ______.
     Answer: Freezing point


  22. The direct conversion of solid into gas without becoming liquid is called ______.
     Answer: Sublimation


  23. The reverse of sublimation is called ______.
     Answer: Deposition


  24. Camphor and iodine show the property of ______.
     Answer: Sublimation


  25. Solids are ______ and have a definite shape.
     Answer: Rigid


  26. Liquids are not rigid but can ______.
     Answer: Flow


  27. Gases have no shape and can ______ to fill the entire container.
     Answer: Expand


  28. Interparticle space in solids is ______.
     Answer: Minimum


  29. Interparticle space in gases is ______.
     Answer: Maximum


  30. Interparticle force in solids is ______.
     Answer: Strong


  31. Interparticle force in gases is ______.
     Answer: Negligible


  32. Matter can change its state by changing ______ or pressure.
     Answer: Temperature


  33. The Kinetic Theory of Matter explains the behaviour of ______.
     Answer: Particles


  34. The law that states mass can neither be created nor destroyed is called ______.
     Answer: Law of Conservation of Mass


  35. Landolt’s experiment proves the ______.
     Answer: Law of Conservation of Mass


  36. Water freezes at ______.
     Answer: 0°C


  37. Water boils at ______.
     Answer: 100°C


  38. Ice melts at ______.
     Answer: 0°C


  39. Conversion of water vapour to water is ______.
     Answer: Condensation


  40. Conversion of water to water vapour is ______.
     Answer: Evaporation


  41. LPG is stored as a liquid under high ______.
     Answer: Pressure


  42. The particles of a gas are ______ spaced.
     Answer: Widely


  43. Solids are not ______.
     Answer: Compressible


  44. Liquids are slightly ______.
     Answer: Compressible


  45. Gases are highly ______.
     Answer: Compressible


  46. All physical substances are made up of ______.
     Answer: Matter


  47. Water in solid state is known as ______.
     Answer: Ice


  48. Water in gaseous state is known as ______.
     Answer: Steam


  49. The particles of matter attract each other due to ______.
     Answer: Intermolecular force


  50. The amount of matter present in a body is called its ______.
     Answer: Mass

Name the Following

  1. Name the physical substance that occupies space and has mass.
     Answer: Matter


  2. Name the smallest unit of matter.
     Answer: Particle


  3. Name the state of matter with a definite shape and volume.
     Answer: Solid


  4. Name the state of matter that has definite volume but no definite shape.
     Answer: Liquid


  5. Name the state of matter with neither definite shape nor volume.
     Answer: Gas


  6. Name the theory that explains the behaviour of matter based on particle motion.
     Answer: Kinetic Theory of Matter


  7. Name the process by which a solid changes into a liquid.
     Answer: Melting


  8. Name the fixed temperature at which a solid melts.
     Answer: Melting point


  9. Name the process by which a liquid changes into gas.
     Answer: Evaporation


  10. Name the fixed temperature at which a liquid boils.
     Answer: Boiling point


  11. Name the process by which gas changes into liquid.
     Answer: Condensation


  12. Name the fixed temperature at which condensation occurs.
     Answer: Condensation point


  13. Name the process by which gas changes to liquid by applying pressure or cooling.
     Answer: Liquefaction


  14. Name the process by which a liquid changes into a solid.
     Answer: Freezing


  15. Name the fixed temperature at which a liquid freezes.
     Answer: Freezing point


  16. Name the process in which a solid changes directly into gas.
     Answer: Sublimation


  17. Name the process in which gas changes directly into solid.
     Answer: Deposition


  18. Name two substances that undergo sublimation.
     Answer: Camphor and Iodine


  19. Name the invisible form of water that rises on heating.
     Answer: Water vapour


  20. Name the visible form of condensed water vapour.
     Answer: Steam


  21. Name the term used for the force of attraction between particles.
     Answer: Intermolecular force


  22. Name the space between the particles of matter.
     Answer: Interparticle space


  23. Name the property of gases that allows them to be compressed easily.
     Answer: Compressibility


  24. Name the scientist whose experiment proved the Law of Conservation of Mass.
     Answer: Landolt


  25. Name the law which states that mass can neither be created nor destroyed.
     Answer: Law of Conservation of Mass


  26. Name the unit used to measure temperature in experiments.
     Answer: Degree Celsius (°C)


  27. Name the physical property of matter that resists change in shape.
     Answer: Rigidity


  28. Name the property of liquids and gases that allows them to flow.
     Answer: Fluidity


  29. Name the process that converts liquid to gas without boiling.
     Answer: Evaporation


  30. Name the physical state of matter with maximum kinetic energy.
     Answer: Gas


  31. Name the physical state of matter with minimum kinetic energy.
     Answer: Solid


  32. Name the process by which solid carbon dioxide turns directly into gas.
     Answer: Sublimation


  33. Name the scientific term for dry ice.
     Answer: Solid carbon dioxide


  34. Name the device used to demonstrate the Law of Conservation of Mass.
     Answer: Landolt’s apparatus


  35. Name the change of state that occurs when ice melts.
     Answer: Melting


  36. Name the change of state that occurs when water freezes.
     Answer: Freezing


  37. Name the change of state that occurs when water boils.
     Answer: Evaporation


  38. Name the change of state that occurs when steam cools.
     Answer: Condensation


  39. Name one physical change involving state of matter.
     Answer: Melting of ice


  40. Name the most compressible state of matter.
     Answer: Gas


  41. Name the least compressible state of matter.
     Answer: Solid


  42. Name one change of state that involves both heating and particle separation.
     Answer: Boiling


  43. Name one change of state that involves cooling and particle closeness.
     Answer: Condensation


  44. Name the energy responsible for particle motion.
     Answer: Heat energy


  45. Name the property of matter which makes it occupy space.
     Answer: Volume


  46. Name the property that determines the heaviness of an object.
     Answer: Mass


  47. Name the state of matter that flows easily and has no fixed volume.
     Answer: Gas


  48. Name the term for direct change from liquid to gas at boiling point.
     Answer: Boiling


  49. Name the solid form of water.
     Answer: Ice


  50. Name the gaseous form of water.
     Answer: Water vapour

Answer in One Word

  1. What is anything that has mass and occupies space?
     Answer: Matter


  2. What are the tiny units that make up matter?
     Answer: Particles


  3. Which state of matter has a fixed shape and volume?
     Answer: Solid


  4. Which state of matter flows but has a fixed volume?
     Answer: Liquid


  5. Which state of matter has neither fixed shape nor volume?
     Answer: Gas


  6. What is the force of attraction between particles called?
     Answer: Intermolecular


  7. What is the space between particles called?
     Answer: Interparticle


  8. What do we call the process of solid turning into liquid?
     Answer: Melting


  9. What is the temperature at which a solid melts?
     Answer: Melting point


  10. What is the process where liquid changes to gas at surface level?
     Answer: Evaporation


  11. What is the temperature at which a liquid boils?
     Answer: Boiling point


  12. What is the process by which gas turns into liquid?
     Answer: Condensation


  13. What is the temperature at which gas condenses?
     Answer: Condensation point


  14. What is gas turning into liquid under pressure called?
     Answer: Liquefaction


  15. What is the process where liquid turns to solid?
     Answer: Freezing


  16. What is the fixed temperature at which a liquid freezes?
     Answer: Freezing point


  17. What is the direct conversion of solid into gas called?
     Answer: Sublimation


  18. What is the reverse of sublimation called?
     Answer: Deposition


  19. What kind of change is melting of ice?
     Answer: Physical


  20. What is the solid form of water?
     Answer: Ice


  21. What is the gaseous form of water?
     Answer: Steam


  22. Which state of matter is highly compressible?
     Answer: Gas


  23. Which state of matter is least compressible?
     Answer: Solid


  24. Which state of matter has maximum kinetic energy?
     Answer: Gas


  25. Which state of matter has minimum kinetic energy?
     Answer: Solid


  26. What kind of change is boiling of water?
     Answer: Physical


  27. What is the invisible form of water vapour called?
     Answer: Steam


  28. What is the visible condensed form of steam?
     Answer: Water


  29. Which property allows gases to expand and fill containers?
     Answer: Compressibility


  30. What energy causes increase in particle movement?
     Answer: Heat


  31. What is the scientific term for dry ice?
     Answer: Carbon dioxide


  32. What property makes solids retain shape?
     Answer: Rigidity


  33. What is the term for matter’s ability to flow?
     Answer: Fluidity


  34. What kind of matter resists applied force the most?
     Answer: Solid


  35. What is the name of the law that states mass is conserved?
     Answer: Conservation


  36. What instrument is used to prove conservation of mass?
     Answer: Landolt’s apparatus


  37. What kind of energy do particles possess due to motion?
     Answer: Kinetic


  38. What is the scientific study of matter called?
     Answer: Chemistry


  39. What is the melting point of ice in Celsius?
     Answer: 0°C


  40. What is the boiling point of water in Celsius?
     Answer: 100°C


  41. What change occurs when steam becomes water?
     Answer: Condensation


  42. What property of liquids allows them to take shape of container?
     Answer: Fluidity


  43. What do we call matter that takes shape and expands easily?
     Answer: Gas


  44. What do you call matter in the form of air?
     Answer: Gas


  45. What property is defined as the amount of matter in a body?
     Answer: Mass


  46. What do we call substances that sublime on heating?
     Answer: Sublimates


  47. What do we call the heat-induced change of solid to liquid?
     Answer: Fusion


  48. What property determines the amount of space occupied?
     Answer: Volume


  49. What are camphor and iodine examples of?
     Answer: Sublimates


  50. What is the branch of science dealing with matter and its changes?
     Answer: Chemistry

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Find the Odd Man Out

  1. Solid, Liquid, Gas, Light
     Answer: Light
     Explanation: Light is not matter; it has no mass or volume.


  2. Ice, Steam, Water, Salt
     Answer: Salt
     Explanation: Salt does not represent a state of water.


  3. Camphor, Iodine, Naphthalene, Water
     Answer: Water
     Explanation: Water does not undergo sublimation; the others do.


  4. Melting, Boiling, Freezing, Rusting
     Answer: Rusting
     Explanation: Rusting is a chemical change; the others are physical changes.


  5. Matter, Energy, Solid, Liquid
     Answer: Energy
     Explanation: Energy is not matter.


  6. Ice, Wood, Stone, Air
     Answer: Air
     Explanation: Air is a gas; the others are solids.


  7. Boiling, Evaporation, Condensation, Photosynthesis
     Answer: Photosynthesis
     Explanation: Photosynthesis is a chemical process; the others are physical.


  8. Solid, Liquid, Gas, Temperature
     Answer: Temperature
     Explanation: Temperature is a condition, not a state of matter.


  9. Camphor, Salt, Iodine, Dry Ice
     Answer: Salt
     Explanation: Salt does not sublime; the others do.


  10. Density, Mass, Volume, Sublimation
     Answer: Sublimation
     Explanation: Sublimation is a process; the others are properties of matter.


  11. Fusion, Condensation, Freezing, Magnetism
     Answer: Magnetism
     Explanation: Magnetism is a physical phenomenon, not a change of state.


  12. Water, Steam, Air, Smoke
     Answer: Smoke
     Explanation: Smoke is a mixture of solid particles and gas; the rest are pure substances.


  13. Bunsen burner, Beaker, Ice cube, Flask
     Answer: Ice cube
     Explanation: Ice cube is matter under study; others are lab apparatus.


  14. Melting point, Freezing point, Boiling point, Break point
     Answer: Break point
     Explanation: Break point is not related to state changes of matter.


  15. Boiling, Melting, Painting, Freezing
     Answer: Painting
     Explanation: Painting is not a state change.


  16. Temperature, Pressure, Time, Volume
     Answer: Time
     Explanation: Time is not a factor affecting the state of matter.


  17. Steam, Water vapour, Oxygen, Ice
     Answer: Ice
     Explanation: Ice is solid; others are gases.


  18. Landolt’s apparatus, Beaker, Tongs, Law
     Answer: Law
     Explanation: Law is a principle; others are apparatus.


  19. Boiling, Freezing, Sublimation, Cooking
     Answer: Cooking
     Explanation: Cooking is a chemical change; others are physical.


  20. Iron, Glass, Camphor, Copper
     Answer: Camphor
     Explanation: Camphor sublimes; others do not.


  21. Water, Oil, Petrol, Ice
     Answer: Ice
     Explanation: Ice is solid; others are liquids.


  22. Volume, Mass, Density, Boiling
     Answer: Boiling
     Explanation: Boiling is a process; others are properties.


  23. Fusion, Freezing, Gravity, Sublimation
     Answer: Gravity
     Explanation: Gravity is a force, not a phase change.


  24. Melting point, Sublimation point, Condensation point, Flash point
     Answer: Flash point
     Explanation: Flash point is related to flammability, not state changes.


  25. LPG, CNG, Air, Camphor
     Answer: Camphor
     Explanation: Camphor is solid; others are gases.


  26. Rusting, Melting, Freezing, Evaporation
     Answer: Rusting
     Explanation: Rusting is a chemical change.


  27. Compressibility, Rigidity, Fluidity, Photosynthesis
     Answer: Photosynthesis
     Explanation: Photosynthesis is not a property of matter.


  28. Liquid, Vapour, Gas, Solid
     Answer: Vapour
     Explanation: Vapour is not a state but a form of gas.


  29. Volume, Shape, Force, Mass
     Answer: Force
     Explanation: Force is not a property of matter.


  30. Oil, Milk, Petrol, Wood
     Answer: Wood
     Explanation: Wood is solid; others are liquids.


  31. Heat, Ice, Air, Water
     Answer: Heat
     Explanation: Heat is energy, not matter.


  32. Evaporation, Melting, Boiling, Combustion
     Answer: Combustion
     Explanation: Combustion is a chemical change.


  33. Mass, Energy, Volume, Density
     Answer: Energy
     Explanation: Energy is not matter.


  34. Solid, Solution, Gas, Liquid
     Answer: Solution
     Explanation: Solution is a mixture, not a state of matter.


  35. Fusion, Liquefaction, Sublimation, Radiation
     Answer: Radiation
     Explanation: Radiation is not a state change.


  36. Ice, Water, Steam, Hydrogen
     Answer: Hydrogen
     Explanation: Hydrogen is an element; others are forms of water.


  37. Kinetic energy, Potential energy, Boiling point, Heat energy
     Answer: Boiling point
     Explanation: Boiling point is a temperature, not energy.


  38. Flask, Landolt’s apparatus, Balance, Rust
     Answer: Rust
     Explanation: Rust is matter; others are apparatus.


  39. Sublimation, Freezing, Heating, Condensation
     Answer: Heating
     Explanation: Heating is a process, not a phase change.


  40. Water, Air, Glass, Sugar
     Answer: Air
     Explanation: Air is gaseous; others are solids or liquids.


  41. Condensation, Freezing, Gravity, Melting
     Answer: Gravity
     Explanation: Gravity is not a phase change.


  42. Density, Viscosity, Volume, Evaporation
     Answer: Evaporation
     Explanation: Evaporation is a process; others are measurable properties.


  43. Dry ice, Camphor, Naphthalene, Vinegar
     Answer: Vinegar
     Explanation: Vinegar does not sublime.


  44. Solid, Gas, Liquid, Plasma
     Answer: Plasma
     Explanation: Plasma is not included in basic ICSE states of matter.


  45. Boiling, Freezing, Heating, Condensation
     Answer: Heating
     Explanation: Heating is a cause, not a phase change.


  46. Oil, Water, Mercury, Glass
     Answer: Glass
     Explanation: Glass is a solid; others are liquids.


  47. Weight, Mass, Volume, Temperature
     Answer: Temperature
     Explanation: Temperature is not a physical quantity of matter itself.


  48. Freezing, Cooking, Boiling, Melting
     Answer: Cooking
     Explanation: Cooking is a chemical change.


  49. Water, Camphor, Iodine, Naphthalene
     Answer: Water
     Explanation: Water does not sublime.


  50. Matter, Substance, Volume, Light
     Answer: Light
     Explanation: Light is not matter.

Match the Pair

Set 1: Match the Pair 

  1. Solid
  2. Liquid
  3. Gas
  4. Matter
  5. Kinetic Theory
  1. Occupies all available space
    B. Particles in constant motion
    C. Tightly packed particles
     D. No fixed shape, but fixed volume
     E. Anything with mass and volume

Answers:
 1 → C
 2 → D
 3 → A
 4 → E
 5 → B



Set 2: Match the Pair 

  1. Melting
  2. Boiling
  3. Freezing
  4. Condensation
  5. Evaporation
  1. Liquid to solid
    B. Gas to liquid
    C. Solid to liquid
     D. Liquid to gas below boiling point
     E. Liquid to gas at boiling point

Answers:
 1 → C
 2 → E
 3 → A
 4 → B
 5 → D



Set 3: Match the Pair 

  1. Sublimation
  2. Interparticle space
  3. Intermolecular force
  4. Plasma
  5. Rigidity
  1. High energy ionised state
    B. Solid to gas without becoming liquid
    C. Fixed shape and resistance to deformation
     D. Space between particles
     E. Force between particles

Answers:
 1 → B
 2 → D
 3 → E
 4 → A
 5 → C



Set 4: Match the Pair 

  1. Ice
  2. Steam
  3. Water
  4. Camphor
  5. Dry ice
  1. Gaseous state of water
    B. Sublimes on heating
    C. Solid CO₂
     D. Solid state of water
     E. Liquid state of water

Answers:
 1 → D
 2 → A
 3 → E
 4 → B
 5 → C



Set 5: Match the Pair 

  1. Boiling point
  2. Melting point
  3. Freezing point
  4. Condensation point
  5. Sublimation point
  1. Temperature at which gas turns to liquid
    B. Temperature at which liquid freezes
    C. Temperature at which liquid boils
     D. Temperature at which solid becomes gas
     E. Temperature at which solid melts

Answers:
 1 → C
 2 → E
 3 → B
 4 → A
 5 → D



Set 6: Match the Pair 

  1. Solid
  2. Liquid
  3. Gas
  4. Vapour
  5. Volume
  1. Space occupied by matter
    B. Takes shape of container
    C. Can be compressed easily
     D. Tightly packed particles
     E. Gaseous form of substance below boiling point

Answers:
 1 → D
 2 → B
 3 → C
 4 → E
 5 → A



Set 7: Match the Pair 

  1. Law of Conservation of Mass
  2. Landolt’s apparatus
  3. Kinetic energy
  4. Temperature
  5. Experiment
  1. Measures degree of heat
    B. Proves mass is neither created nor destroyed
    C. Energy due to motion
     D. Scientific procedure
     E. Setup to prove mass conservation

Answers:
 1 → B
 2 → E
 3 → C
 4 → A
 5 → D



Set 8: Match the Pair 

  1. Ice melts
  2. Water boils
  3. Steam condenses
  4. Water freezes
  5. Camphor sublimes
  1. Gas to liquid
    B. Solid to gas
    C. Solid to liquid
     D. Liquid to solid
     E. Liquid to gas

Answers:
 1 → C
 2 → E
 3 → A
 4 → D
 5 → B



Set 9: Match the Pair 

  1. Flow
  2. Compressibility
  3. Density
  4. Mass
  5. Shape
  1. Resistance to compression
    B. Measure of matter in an object
    C. Ability to move and take container’s shape
     D. Compactness of particles
     E. Physical boundary of an object

Answers:
 1 → C
 2 → A
 3 → D
 4 → B
 5 → E



Set 10: Match the Pair 

  1. Matter
  2. Energy
  3. Air
  4. Wood
  5. Steam
  1. Gaseous state of water
    B. Occupies space and has mass
    C. Not matter
     D. Mixture of gases
     E. Solid form of matter

Answers:
 1 → B
 2 → C
 3 → D
 4 → E
 5 → A

Short Answer Questions  

  1. What is matter?
     Answer: Matter is anything that occupies space and has mass.


  2. Name the three physical states of matter.
     Answer: Solid, liquid, and gas.


  3. What are the particles of matter constantly doing?
     Answer: The particles of matter are constantly moving.


  4. What is the force of attraction between particles called?
     Answer: It is called intermolecular force.


  5. What is the space between particles of matter called?
     Answer: It is called interparticle space.


  6. Which state of matter has the strongest intermolecular force?
     Answer: Solid.


  7. Which state of matter has the weakest intermolecular force?
     Answer: Gas.


  8. What is the term for the energy possessed by particles due to motion?
     Answer: Kinetic energy.


  9. Why are gases highly compressible?
     Answer: Because they have large interparticle spaces.


  10. Why do solids have fixed shape and volume?
     Answer: Due to strong intermolecular forces and closely packed particles.


  11. Why do liquids take the shape of the container?
     Answer: Because their particles can slide over each other.


  12. Why do gases occupy the entire available space?
     Answer: Because their particles move freely in all directions.


  13. What is meant by sublimation?
     Answer: Sublimation is the change of state from solid directly to gas.


  14. Name two substances that undergo sublimation.
     Answer: Camphor and iodine.


  15. What is melting?
     Answer: Melting is the process by which a solid changes to a liquid.


  16. What is boiling?
     Answer: Boiling is the process by which a liquid changes to gas at its boiling point.


  17. What is evaporation?
     Answer: Evaporation is the slow conversion of liquid to gas at its surface.


  18. What is condensation?
     Answer: Condensation is the process of gas changing into liquid.


  19. What is freezing?
     Answer: Freezing is the process of a liquid changing into a solid.


  20. What is liquefaction?
     Answer: Liquefaction is the process of converting a gas into a liquid by cooling or applying pressure.


  21. What is the melting point of ice?
     Answer: 0°C.


  22. What is the boiling point of water?
     Answer: 100°C.


  23. What is the freezing point of water?
     Answer: 0°C.


  24. What is the condensation point of steam?
     Answer: 100°C.


  25. Define volume.
     Answer: Volume is the amount of space occupied by matter.


  26. Define mass.
     Answer: Mass is the quantity of matter in an object.


  27. What does the Kinetic Theory of Matter state?
     Answer: It states that matter is made up of small particles which are in constant motion.


  28. What is plasma?
     Answer: Plasma is a high-energy ionised state of matter.


  29. What is a physical change?
     Answer: A physical change is a change in state or appearance without forming a new substance.


  30. Is boiling a physical or chemical change?
     Answer: Boiling is a physical change.


  31. Is rusting a physical or chemical change?
     Answer: Rusting is a chemical change.


  32. Which state of matter has no definite shape or volume?
     Answer: Gas.


  33. Which state of matter is rigid and incompressible?
     Answer: Solid.


  34. Why do liquids have a definite volume?
     Answer: Because their particles are held together with moderate force.


  35. What happens to particle motion when temperature increases?
     Answer: Particle motion increases.


  36. What happens to the interparticle space when matter is heated?
     Answer: It increases.


  37. What is the effect of applying pressure on gases?
     Answer: It compresses them into a smaller volume.


  38. What is meant by interconversion of states of matter?
     Answer: It is the change of one state of matter to another by changing temperature or pressure.


  39. Name the change of state from gas to solid directly.
     Answer: Deposition.


  40. What is vapour?
     Answer: Vapour is the gaseous form of a substance below its boiling point.


  41. Which process converts vapour to liquid?
     Answer: Condensation.


  42. Which instrument is used to prove the Law of Conservation of Mass?
     Answer: Landolt’s apparatus.


  43. State the Law of Conservation of Mass.
     Answer: Mass can neither be created nor destroyed in a chemical reaction.


  44. What kind of change is sublimation?
     Answer: Sublimation is a physical change.


  45. Name a property that allows gases to fill a container completely.
     Answer: Compressibility.


  46. Why does steam cause more severe burns than boiling water?
     Answer: Because steam contains latent heat of vaporisation.


  47. What type of energy increases during heating?
     Answer: Kinetic energy.


  48. Which process is the opposite of melting?
     Answer: Freezing.


  49. Which process is the opposite of evaporation?
     Answer: Condensation.


  50. Which state of matter has maximum kinetic energy?
     Answer: Gas.

Puzzles

  1. I am a state of matter, very rigid and dense. I have a fixed shape. What am I?
    Answer: Solid

 

  1. Unscramble: RATMTE
    Answer: Matter

 

  1. I am the process where a solid becomes a liquid. What am I?
    Answer: Melting

 

  1. I vanish into thin air without becoming liquid. I am a solid. What am I?
    Answer: Camphor

 

  1. I am the force that holds particles together. What am I?
    Answer: Intermolecular force

 

  1. Unscramble: OBLNIGI
    Answer: Boiling

 

  1. I am a change where no new substance forms, just a change of state. What am I?
    Answer: Physical change

 

  1. I change from liquid to gas at the surface at all temperatures. What am I?
    Answer: Evaporation

 

  1. Find me: I am the fixed temperature where a liquid becomes gas.
    Answer: Boiling point

 

  1. What state am I in? I expand to fill any container and have no fixed shape or volume.
    Answer: Gas

 

  1. I am known as dry ice. What is my chemical name?
    Answer: Solid carbon dioxide

 

  1. Unscramble: ZTAREPUMERE
    Answer: Temperature

 

  1. I am the process where a gas turns into a liquid. What am I?
    Answer: Condensation

 

  1. You find me only when a solid directly becomes a gas. What process am I?
    Answer: Sublimation

 

  1. I represent the energy of motion. What am I?
    Answer: Kinetic energy

 

  1. I am the space between particles in matter. What am I called?
    Answer: Interparticle space

 

  1. My name sounds like a crime, but I am a phase change from liquid to solid. What am I?
    Answer: Freezing

 

  1. What do the following have in common: Iodine, Naphthalene, Camphor?
    Answer: They undergo sublimation.

 

  1. I’m measured in degrees Celsius. I rise when you heat something. What am I?
    Answer: Temperature

 

  1. I prove mass is never lost or gained during reactions. I am a law. What am I?
    Answer: Law of Conservation of Mass

 

  1. Unscramble: FEIRNEZG
    Answer: Freezing

 

  1. I am invisible, yet I exist. I have mass and occupy space. I am all around you. What am I?
    Answer: Air

 

  1. I occur at 0°C for water and change liquid to solid. What am I?
    Answer: Freezing point

 

  1. I am the form of water at 100°C but I’m invisible. What am I?
    Answer: Water vapour

 

  1. Odd one out: Solid, Liquid, Steam, Gas
    Answer: Steam (It’s a form of water; others are general states)

 

  1. Odd one out: Boiling, Condensation, Rusting, Evaporation
    Answer: Rusting (It’s a chemical change)

 

  1. Which state of matter fits all clues? Can flow, fixed volume, takes container shape.
    Answer: Liquid

 

  1. I am a solid with particles tightly packed and cannot be compressed. What am I?
    Answer: Solid

 

  1. Riddle: I’m made up of particles, yet you can’t see me. I spread out and fill everything. What am I?
    Answer: Gas

 

  1. Unscramble: ONSSNCDOEATI
    Answer: Condensation

 

  1. I’m a white solid, I disappear into vapour without melting. I’m used in mothballs. What am I?
    Answer: Naphthalene

 

  1. Rearrange: CEI → ? (Changes state when heated)
    Answer: Ice → Water

 

  1. Find the process: Liquid → Gas (with heating, throughout liquid)
    Answer: Boiling

 

  1. Find the process: Gas → Liquid (with cooling)
    Answer: Condensation

 

  1. Rearranged letters: LAWS OF MASS CONSERVATION (clue: proven by Landolt’s experiment)
    Answer: Law of Conservation of Mass

 

  1. I make your sweat disappear and cool you down. What am I?
    Answer: Evaporation

 

  1. My particles vibrate but don’t move from place. What am I?
    Answer: Solid

 

  1. Riddle: I’m a form of water, yet I burn more than boiling water. What am I?
    Answer: Steam

 

  1. Odd one out: Camphor, Water, Iodine, Naphthalene
    Answer: Water (Does not sublime)

 

  1. Find the change: Reversible, no new substance, change of state.
    Answer: Physical change

 

  1. Rearranged clue: AMEELTNGIPONT (Hint: Ice starts turning to water here)
    Answer: Melting point

 

  1. I result from cooling water vapour. I am visible on glass. What am I?
    Answer: Droplets (via condensation)

 

  1. Identify the process: Solid → Gas → Solid
    Answer: Sublimation and Deposition

 

  1. I am used in an experiment to prove that total mass is unchanged. What apparatus am I?
    Answer: Landolt’s apparatus

 

  1. Which property do solids have but gases don’t?
    Answer: Definite shape

 

  1. Unscramble: DILQIU
    Answer: Liquid

 

  1. Odd one out: Boiling, Condensation, Freezing, Combustion
    Answer: Combustion (Chemical change)

 

  1. I happen faster when heat is added and air moves. What am I?
    Answer: Evaporation

 

  1. Identify the process: Particles lose energy and become fixed.
    Answer: Freezing

 

  1. Complete the sequence: Solid → Liquid → ?
    Answer: Gas

Difference Between:

  1. Difference between Solid and Liquid
  • Solids have a definite shape and volume.
  • Liquids have a definite volume but no definite shape; they take the shape of the container.

 

  1. Difference between Liquid and Gas
  • Liquids have a fixed volume and are slightly compressible.
  • Gases have neither fixed shape nor volume and are highly compressible.

 

  1. Difference between Boiling and Evaporation
  • Boiling occurs at a fixed temperature (boiling point) throughout the liquid.
  • Evaporation occurs at all temperatures only from the surface of the liquid.

 

  1. Difference between Melting and Freezing
  • Melting is the change of state from solid to liquid by heating.
  • Freezing is the change of state from liquid to solid by cooling.

 

  1. Difference between Condensation and Evaporation
  • Condensation is the conversion of gas to liquid by cooling.
  • Evaporation is the conversion of liquid to gas at room temperature.

 

  1. Difference between Physical Change and Chemical Change
  • Physical change does not produce a new substance and is reversible.
  • Chemical change forms a new substance and is usually irreversible.

 

  1. Difference between Matter and Mass
  • Matter is anything that has mass and occupies space.
  • Mass is the quantity of matter contained in an object.

 

  1. Difference between Interparticle Space and Intermolecular Force
  • Interparticle space is the gap between particles of matter.
  • Intermolecular force is the force of attraction between particles.

 

  1. Difference between Melting Point and Boiling Point
  • Melting point is the temperature at which a solid changes to liquid.
  • Boiling point is the temperature at which a liquid changes to gas.

 

  1. Difference between Solids and Gases
  • Solids have fixed shape and volume, are incompressible.
  • Gases have no fixed shape or volume and are highly compressible.

 

  1. Difference between Law of Conservation of Mass and Law of Constant Proportions
  • Law of Conservation of Mass states that total mass remains constant during a reaction.
  • Law of Constant Proportions states that a compound always contains elements in a fixed ratio by mass.

 

  1. Difference between Kinetic Energy and Potential Energy (in context of matter)
  • Kinetic energy is energy due to motion of particles.
  • Potential energy is stored energy due to position or arrangement of particles.

 

  1. Difference between Shape and Volume
  • Shape refers to the outer form or boundary of a substance.
  • Volume is the amount of space occupied by the substance.

 

  1. Difference between Sublimation and Boiling
  • Sublimation is the direct change from solid to gas.
  • Boiling is the change from liquid to gas at boiling point.

 

  1. Difference between Ice and Water Vapour
  • Ice is the solid state of water with fixed shape and volume.
  • Water vapour is the gaseous state of water with no fixed shape or volume.

 

  1. Difference between Rigid and Fluid States
  • Rigid states (like solids) resist change in shape and volume.
  • Fluid states (like liquids and gases) can flow and take the shape of the container.

 

  1. Difference between Plasma and Gas
  • Plasma is a high-energy ionised state of matter with free electrons.
  • Gas is a neutral state of matter with particles moving freely.

 

  1. Difference between Volume and Density
  • Volume is the space occupied by matter.
  • Density is the mass of matter per unit volume.

 

  1. Difference between Sublimation and Deposition
  • Sublimation is the change from solid to gas.
  • Deposition is the change from gas to solid.

 

  1. Difference between Heating and Boiling
  • Heating is the process of increasing temperature.
  • Boiling is a specific point where liquid changes to gas with bubble formation throughout.

Assertion and Reason

Key to options:
 A. Both Assertion and Reason are true, and Reason is the correct explanation of Assertion.
 B. Both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
 C. Assertion is true, but Reason is false.
 D. Assertion is false, but Reason is true.


  1. Assertion: Matter occupies space and has mass.
     Reason: Matter is made up of particles.
     Answer: B


  2. Assertion: Solids have definite shape.
     Reason: The particles in solids are tightly packed and vibrate about fixed positions.
     Answer: A


  3. Assertion: Liquids do not have a fixed shape.
     Reason: The particles in liquids are loosely packed and can slide over one another.
     Answer: A


  4. Assertion: Gases are compressible.
     Reason: Gases have large interparticle spaces.
     Answer: A


  5. Assertion: Particles of matter are in continuous motion.
     Reason: The kinetic theory of matter states that all matter is composed of stationary particles.
     Answer: C


  6. Assertion: Interparticle force of attraction is strong in solids.
     Reason: Particles in solids are very far apart.
     Answer: C


  7. Assertion: Gases have a definite shape.
     Reason: Gases can be compressed and occupy all available space.
     Answer: D


  8. Assertion: Evaporation is a surface phenomenon.
     Reason: Only the surface particles gain enough energy to escape as gas.
     Answer: A


  9. Assertion: Sublimation is a physical change.
     Reason: It involves change of state without forming a new substance.
     Answer: A


  10. Assertion: Water boils at 100°C under standard atmospheric pressure.
     Reason: At this temperature, the vapour pressure of water equals the atmospheric pressure.
     Answer: A


  11. Assertion: Liquids can be compressed easily.
     Reason: Liquids have very large intermolecular spaces.
     Answer: C


  12. Assertion: Steam at 100°C causes more severe burns than boiling water at 100°C.
     Reason: Steam contains additional latent heat of vaporisation.
     Answer: A


  13. Assertion: Solids are less dense than gases.
     Reason: Solids have more interparticle space than gases.
     Answer: D


  14. Assertion: Camphor changes directly from solid to vapour.
     Reason: Camphor shows the property of sublimation.
     Answer: A


  15. Assertion: All changes of state are chemical changes.
     Reason: New substances are always formed during a change of state.
     Answer: D


  16. Assertion: Water can exist in all three physical states.
     Reason: Water vapour, liquid water, and ice are physical states of the same substance.
     Answer: A


  17. Assertion: Melting of ice is a reversible change.
     Reason: Ice can melt into water and water can freeze into ice.
     Answer: A


  18. Assertion: The boiling point of a liquid depends on atmospheric pressure.
     Reason: Boiling occurs when the vapour pressure equals the atmospheric pressure.
     Answer: A


  19. Assertion: Interconversion of states of matter is a chemical change.
     Reason: The identity of matter changes during interconversion.
     Answer: D


  20. Assertion: Dry ice is the solid form of carbon dioxide.
     Reason: It sublimes directly into carbon dioxide gas.
     Answer: A


  21. Assertion: Matter does not have mass.
     Reason: Matter cannot be seen with the naked eye.
     Answer: D


  22. Assertion: Gases have high kinetic energy.
     Reason: The particles in gases move freely and rapidly.
     Answer: A


  23. Assertion: Boiling is a rapid process that occurs throughout the liquid.
     Reason: Boiling involves formation of vapour bubbles inside the liquid.
     Answer: A


  24. Assertion: Freezing of water is a physical change.
     Reason: No new substance is formed.
     Answer: A


  25. Assertion: The freezing point of pure water is 0°C.
     Reason: Water freezes at this temperature under normal atmospheric pressure.
     Answer: A


  26. Assertion: Sublimation involves the liquid state.
     Reason: In sublimation, a solid changes directly into a gas without becoming liquid.
     Answer: C


  27. Assertion: Intermolecular forces are negligible in gases.
     Reason: Particles in gases are very far apart.
     Answer: A


  28. Assertion: Volume is the amount of space occupied by matter.
     Reason: Matter occupies space and has mass.
     Answer: B


  29. Assertion: Landolt’s apparatus proves the Law of Conservation of Mass.
     Reason: Total mass remains unchanged in a closed system during a physical or chemical change.
     Answer: A


  30. Assertion: Liquids have a fixed shape.
     Reason: The particles in liquids are tightly bound and cannot move.
     Answer: D


  31. Assertion: Temperature does not affect particle movement.
     Reason: Heat increases kinetic energy of particles.
     Answer: C


  32. Assertion: Energy is matter.
     Reason: Energy occupies space and has mass.
     Answer: D


  33. Assertion: Mass is conserved during chemical reactions.
     Reason: The Law of Conservation of Mass is always followed in chemical reactions.
     Answer: A


  34. Assertion: Evaporation occurs only at the boiling point.
     Reason: Particles in a liquid gain energy and escape at any temperature.
     Answer: C


  35. Assertion: Water can change to vapour below 100°C.
     Reason: Evaporation occurs at all temperatures.
     Answer: A


  36. Assertion: Boiling is a surface phenomenon.
     Reason: Boiling occurs only at the surface of a liquid.
     Answer: D


  37. Assertion: Gases have maximum interparticle space.
     Reason: Gases can be compressed easily.
     Answer: A


  38. Assertion: Liquids can be poured.
     Reason: Liquids have the property of fluidity.
     Answer: A


  39. Assertion: Boiling water and steam at 100°C contain the same amount of energy.
     Reason: Both are at the same temperature.
     Answer: C


  40. Assertion: Ice floats on water.
     Reason: Ice is denser than water.
     Answer: C


  41. Assertion: Gas particles move randomly.
     Reason: They are not bound by strong intermolecular forces.
     Answer: A


  42. Assertion: Matter does not occupy space.
     Reason: Matter has no mass.
     Answer: D


  43. Assertion: Camphor undergoes sublimation.
     Reason: It melts before turning into gas.
     Answer: C


  44. Assertion: Air is not a pure substance.
     Reason: It is a homogeneous mixture of gases.
     Answer: A


  45. Assertion: Solids can flow like liquids.
     Reason: Their particles are free to move.
     Answer: D


  46. Assertion: Water vapour is a solid state of water.
     Reason: It is formed by cooling steam.
     Answer: D


  47. Assertion: In solids, particles vibrate about fixed positions.
     Reason: Solids have maximum intermolecular force of attraction.
     Answer: A


  48. Assertion: Condensation is the conversion of liquid into gas.
     Reason: It occurs by heating the liquid.
     Answer: D


  49. Assertion: Steam causes more severe burns than boiling water.
     Reason: Steam has more energy due to latent heat.
     Answer: A


  50. Assertion: All matter is visible.
     Reason: Particles of matter are large in size.
     Answer: D

True or False

  1. Matter is anything that has mass and occupies space.
     Answer: True


  2. Solids have the weakest intermolecular force of attraction.
     Answer: False


  3. Liquids have a definite volume but no definite shape.
     Answer: True


  4. Gases have both definite shape and volume.
     Answer: False


  5. The particles of matter are stationary.
     Answer: False


  6. Intermolecular space is maximum in solids.
     Answer: False


  7. Gas can be compressed easily.
     Answer: True


  8. Liquids take the shape of the container.
     Answer: True


  9. Solids can flow like liquids.
     Answer: False


  10. Particles of a solid vibrate about their fixed positions.
     Answer: True


  11. Matter does not exist in all forms in nature.
     Answer: False


  12. Sublimation is the change of state from solid to gas.
     Answer: True


  13. Water boils at 0°C.
     Answer: False


  14. Ice melts at 0°C.
     Answer: True


  15. Evaporation occurs only at 100°C.
     Answer: False


  16. Gases are highly compressible due to large intermolecular space.
     Answer: True


  17. Plasma is not considered a state of matter in ICSE syllabus.
     Answer: True


  18. Freezing is a chemical change.
     Answer: False


  19. Melting of ice is a reversible physical change.
     Answer: True


  20. Water exists only in liquid form in nature.
     Answer: False


  21. Boiling and evaporation are two different processes.
     Answer: True


  22. All physical changes are irreversible.
     Answer: False


  23. Condensation is the change of state from gas to liquid.
     Answer: True


  24. Interconversion of states of matter involves physical changes.
     Answer: True


  25. Matter is made up of tiny particles.
     Answer: True


  26. Heat energy increases the movement of particles.
     Answer: True


  27. Solids are more compressible than gases.
     Answer: False


  28. The melting point and freezing point of a substance are usually the same.
     Answer: True


  29. Vapour is the gaseous state of matter below its boiling point.
     Answer: True


  30. Landolt’s experiment proves the Law of Multiple Proportions.
     Answer: False


  31. Mass is not conserved during a physical change.
     Answer: False


  32. The Law of Conservation of Mass applies to both physical and chemical changes.
     Answer: True


  33. Steam is formed when water freezes.
     Answer: False


  34. Water changes into ice by evaporation.
     Answer: False


  35. Condensation is a heating process.
     Answer: False


  36. Boiling involves formation of vapour bubbles throughout the liquid.
     Answer: True


  37. Intermolecular forces are negligible in gases.
     Answer: True


  38. Energy is a form of matter.
     Answer: False


  39. Air is a matter because it occupies space and has mass.
     Answer: True


  40. Liquids are incompressible.
     Answer: False


  41. The particles of a liquid are more loosely packed than those of a solid.
     Answer: True


  42. Steam has more energy than boiling water.
     Answer: True


  43. Particles of matter are not in constant motion.
     Answer: False


  44. Water vapour is the solid state of water.
     Answer: False


  45. The boiling point of water is 100°C at normal atmospheric pressure.
     Answer: True


  46. The freezing of water is a chemical change.
     Answer: False


  47. The gaseous form of water is called steam or water vapour.
     Answer: True


  48. In sublimation, the liquid state is skipped.
     Answer: True


  49. Intermolecular space is minimum in gases.
     Answer: False


  50. Mass is the quantity of matter contained in a body.
     Answer: True

Long Answer Questions

  1. Define matter. Explain its characteristics.
    Answer:
    Matter is anything that has mass and occupies space. It can exist in three physical states: solid, liquid, and gas. The main characteristics of matter are:
  1. Matter is made up of tiny particles.
  2. These particles are in constant motion.
  3. There is space between particles (interparticle space).
  4. Particles of matter attract each other (intermolecular force).

 

  1. Describe the three states of matter with their properties.
    Answer:
    The three states of matter are solid, liquid, and gas.
  • Solids have definite shape and volume, particles are tightly packed, and intermolecular forces are strong.
  • Liquids have definite volume but no fixed shape; particles are loosely packed and can flow.
  • Gases have neither definite shape nor volume; particles are far apart, move freely, and intermolecular forces are negligible.

 

  1. What is the Kinetic Theory of Matter? Mention its postulates.
    Answer:
    The Kinetic Theory of Matter states that all matter is made up of tiny particles which are in constant motion.
     Its main postulates are:
  1. Matter is composed of small particles (atoms or molecules).
  2. Particles are in continuous motion.
  3. There are spaces between particles.
  4. There are forces of attraction between particles.
  5. Increase in temperature increases particle motion (kinetic energy).

 

  1. Differentiate between solids, liquids, and gases based on their properties.
    Answer:
  • Solids: Have definite shape and volume, are incompressible, rigid, and have strong intermolecular forces with minimum interparticle space.
  • Liquids: Have definite volume, no fixed shape, are less compressible, fluid in nature, and have moderate intermolecular forces with more space between particles.
  • Gases: Have neither definite shape nor volume, are highly compressible, have weak intermolecular forces, and maximum interparticle space.

 

  1. Explain interconversion of states of matter with examples.
    Answer:
    Interconversion of states of matter is the process of changing from one state to another by altering temperature or pressure.
  • Melting (solid to liquid), e.g., ice to water.
  • Boiling (liquid to gas), e.g., water to steam.
  • Condensation (gas to liquid), e.g., steam to water.
  • Freezing (liquid to solid), e.g., water to ice.
  • Sublimation (solid to gas directly), e.g., camphor to vapour.
  • Deposition (gas to solid), e.g., water vapour to frost.

 

  1. What is sublimation? Give examples and explain the process.
    Answer:
    Sublimation is the direct change of state from solid to gas without becoming liquid. It occurs in substances like camphor, iodine, and naphthalene. When heated, these solids directly convert into vapour and when cooled, vapours deposit back into solids.

 

  1. Explain how heating and cooling affect the states of matter.
    Answer:
    Heating increases the kinetic energy of particles, causing them to move faster and overcome intermolecular forces. This leads to changes like melting or evaporation. Cooling reduces particle movement, allowing intermolecular forces to pull them closer, leading to freezing or condensation.

 

  1. Describe how pressure affects the states of matter.
    Answer:
    Increasing pressure brings particles closer together, allowing gases to convert into liquids (liquefaction). Decreasing pressure allows liquids to evaporate more easily. LPG is an example where gas is liquefied under pressure and stored in cylinders.

 

  1. What is evaporation? How is it different from boiling?
    Answer:
    Evaporation is the slow conversion of liquid into gas at all temperatures, usually from the surface. Boiling is rapid and occurs at a specific temperature (boiling point). Evaporation occurs below boiling point and doesn’t require heating.

 

  1. Explain the term boiling point. What happens to particles during boiling?
    Answer:
    Boiling point is the fixed temperature at which a liquid changes into gas throughout its body. During boiling, particles gain energy, move rapidly, overcome intermolecular forces, and form bubbles of vapour that rise and escape.

 

  1. What is condensation? Explain with an example.
    Answer:
    Condensation is the process where gas changes into liquid on cooling. Example: steam condensing on a cold surface to form water droplets. It occurs due to loss of heat and decrease in kinetic energy of particles.

 

  1. What is meant by freezing? How does it occur?
    Answer:
    Freezing is the process by which a liquid changes into solid on cooling. As temperature drops, particle motion slows and intermolecular forces pull particles closer, resulting in a fixed structure, e.g., water turning into ice.

 

  1. Define melting and melting point.
    Answer:
    Melting is the process by which a solid changes into a liquid upon heating. The melting point is the fixed temperature at which this change occurs, e.g., ice melts at 0°C.

 

  1. State the Law of Conservation of Mass.
    Answer:
    The Law of Conservation of Mass states that mass can neither be created nor destroyed in a chemical reaction. The total mass of reactants is always equal to the total mass of products in a closed system.

 

  1. Describe the experiment to prove the Law of Conservation of Mass.
    Answer:
    Landolt’s experiment uses a sealed H-shaped tube containing sodium chloride in one limb and silver nitrate in the other. When mixed by shaking, a white precipitate of silver chloride forms, but the total mass remains unchanged, proving the law.

 

  1. Why do solids have definite shape and volume?
    Answer:
    Solids have strong intermolecular forces that keep particles tightly packed in fixed positions, giving them a definite shape and volume.

 

  1. Why are gases highly compressible?
    Answer:
    Gases have large interparticle spaces and very weak intermolecular forces, allowing them to be compressed easily by applying pressure.

 

  1. What are the differences between boiling and evaporation?
    Answer:
    Boiling is fast, occurs at a fixed temperature throughout the liquid, and requires heat. Evaporation is slow, occurs at all temperatures from the surface, and doesn’t need external heat.

 

  1. What is meant by interparticle space and intermolecular force?
    Answer:
    Interparticle space is the distance between particles of matter. Intermolecular force is the attractive force between these particles. The two factors determine the state of matter.

 

  1. Define and explain fluidity.
    Answer:
    Fluidity is the ability of a substance to flow. Liquids and gases possess fluidity because their particles are loosely packed and can move past each other easily.

 

  1. What are the main postulates of the Kinetic Theory of Matter?
    Answer:
    The main postulates are:
  1. Matter is composed of tiny particles.
  2. These particles are in constant motion.
  3. There is space between particles.
  4. Particles attract each other with intermolecular forces.
  5. Temperature increases the kinetic energy and movement of particles.

 

  1. How does temperature affect the kinetic energy of particles?
    Answer:
    An increase in temperature raises the kinetic energy of particles, causing them to move faster and spread apart, which can lead to a change in the state of matter.

 

  1. Explain the difference in particle arrangement in solids, liquids, and gases.
    Answer:
    In solids, particles are tightly packed in fixed positions. In liquids, particles are less tightly packed and can slide past each other. In gases, particles are far apart and move freely in all directions.

 

  1. Why do gases not have a fixed volume?
    Answer:
    Gases have weak intermolecular forces and large interparticle spaces, allowing their particles to spread and occupy any available space, so they don’t have a fixed volume.

 

  1. What is meant by compressibility? How does it vary in the three states of matter?
    Answer:
    Compressibility is the ability to reduce volume under pressure. Solids are incompressible, liquids are slightly compressible, and gases are highly compressible due to maximum interparticle space.

 

  1. Give an example of each: physical change and chemical change.
    Answer:
    Physical change: Melting of ice into water.
     Chemical change: Rusting of iron.

 

  1. Why is the melting of ice considered a physical change?
    Answer:
    Because no new substance is formed, and the process is reversible; only the state of water changes from solid to liquid.

 

  1. Define boiling point and state the boiling point of water.
    Answer:
    Boiling point is the fixed temperature at which a liquid turns into gas throughout its body. For water, it is 100°C at normal atmospheric pressure.

 

  1. Define melting point and state the melting point of ice.
    Answer:
    Melting point is the fixed temperature at which a solid turns into liquid. For ice, the melting point is 0°C.

 

  1. Define freezing point and state the freezing point of water.
    Answer:
    Freezing point is the temperature at which a liquid turns into solid. Water freezes at 0°C.

 

  1. How are evaporation and boiling different in terms of energy and process?
    Answer:
    Evaporation is a slow process that occurs at all temperatures from the surface and does not require extra energy. Boiling is a rapid process that occurs throughout the liquid at a specific temperature and needs continuous heating.

 

  1. What is the significance of interparticle space in determining the state of matter?
    Answer:
    Interparticle space affects particle mobility and compressibility. Smaller space (as in solids) results in rigidity, while larger space (as in gases) leads to fluidity and high compressibility.

 

  1. Explain with an example how a change in pressure can lead to liquefaction.
    Answer:
    By increasing pressure and decreasing temperature, a gas can be liquefied. For example, LPG is stored as liquid under pressure, and when the pressure is released, it turns into gas.

 

  1. What do you understand by the term “vapour”? How is it different from gas?
    Answer:
    Vapour refers to the gaseous state of a substance that exists as a liquid or solid under normal conditions. Gas exists as a gas under normal conditions. E.g., steam is water vapour.

 

  1. What is condensation? How does it occur and give one practical use.
    Answer:
    Condensation is the change of gas to liquid on cooling. It occurs due to loss of kinetic energy. Example: In distillation, vapours are condensed into liquid to separate components.

 

  1. Why is the Law of Conservation of Mass important in chemistry?
    Answer:
    It ensures that in any physical or chemical change, the total mass remains constant, which helps in balancing chemical equations and maintaining stoichiometric ratios.

 

  1. Describe how camphor undergoes sublimation.
    Answer:
    When camphor is heated, it directly changes into vapour without becoming liquid. On cooling, the vapour deposits back to solid, proving it undergoes sublimation.

 

  1. Compare the motion of particles in solids, liquids, and gases.
    Answer:
    In solids, particles vibrate about fixed positions. In liquids, particles move moderately and slide past one another. In gases, particles move rapidly in all directions.

 

  1. What are the uses of sublimation in daily life?
    Answer:
    Sublimation is used in purifying substances like camphor and iodine, in air fresheners (naphthalene balls), and in dry cleaning processes where solid CO₂ is used.

 

  1. How can you prove that air is matter?
    Answer:
    Air occupies space and has mass. It can be compressed, exerts pressure, and adds weight to an inflated balloon, proving it is matter.

 

  1. Explain the term “latent heat.” How is it involved in boiling and melting?
    Answer:
    Latent heat is the energy absorbed or released during a change of state without temperature change. It breaks intermolecular bonds during melting/boiling without raising temperature.

 

  1. What happens to water molecules when it changes to steam?
    Answer:
    Water molecules gain heat, their kinetic energy increases, and they overcome intermolecular forces to spread out and convert into steam (vapour).

 

  1. What is deposition? Give an example.
    Answer:
    Deposition is the direct conversion of gas into solid without becoming liquid. Example: Frost formation from water vapour on a cold surface.

 

  1. Why does steam cause more severe burns than boiling water?
    Answer:
    Because steam contains extra latent heat of vaporisation which releases additional energy on contact with the skin, causing deeper burns.

 

  1. Why is the boiling point of a liquid affected by atmospheric pressure?
    Answer:
    Because boiling occurs when vapour pressure equals atmospheric pressure. Lower pressure (at high altitudes) lowers boiling point, while higher pressure raises it.

 

  1. Differentiate between mass and volume with examples.
    Answer:
    Mass is the quantity of matter (e.g., 2 kg of iron), while volume is the space it occupies (e.g., 1 litre of water). Both are physical properties of matter.

 

  1. How does the arrangement of particles affect the flow property of a substance?
    Answer:
    In fluids like liquids and gases, particles are loosely arranged and can move past each other, allowing them to flow. Solids cannot flow due to fixed particle arrangement.

 

  1. Why is the freezing of water a reversible change?
    Answer:
    Because water can freeze into ice and then melt back into water without forming a new substance, making it a reversible physical change.

 

  1. Why are solids not compressible?
    Answer:
    Because their particles are already tightly packed with very little interparticle space, leaving no room for compression.

 

  1. What happens to the motion and arrangement of particles when a liquid changes to solid?
    Answer:
    Particles lose energy, move slower, come closer, and arrange into fixed positions, forming a rigid structure, thus changing the liquid into a solid.

Give Reasons

  1. Give reason: Solids have a definite shape.
     Answer: Because the particles in solids are tightly packed with strong intermolecular forces, keeping them fixed in position.


  2. Give reason: Liquids can flow.
     Answer: Because the particles in liquids are loosely packed and can slide past one another.


  3. Give reason: Gases have no fixed volume.
     Answer: Because gas particles are far apart and move freely, allowing them to expand and fill any space.


  4. Give reason: Ice melts on heating.
     Answer: Because heating increases the kinetic energy of particles, weakening the intermolecular forces and changing it to liquid.


  5. Give reason: Steam causes more severe burns than boiling water.
     Answer: Because steam contains latent heat of vaporisation, releasing more energy upon condensation.


  6. Give reason: Matter is said to be particulate in nature.
     Answer: Because it is made up of tiny particles that cannot be seen with the naked eye.


  7. Give reason: Gases are highly compressible.
     Answer: Because they have large interparticle spaces and negligible intermolecular forces.


  8. Give reason: Liquids take the shape of the container.
     Answer: Because they do not have a fixed shape and their particles can move and adjust to the container’s boundaries.


  9. Give reason: Solids are not compressible.
     Answer: Because their particles are tightly packed with very little space between them.


  10. Give reason: Particles of matter are said to be in motion.
     Answer: Because they constantly move and exhibit kinetic energy.


  11. Give reason: Interconversion of states of matter is a physical change.
     Answer: Because no new substance is formed and the change is reversible.


  12. Give reason: Boiling is considered a bulk phenomenon.
     Answer: Because it occurs throughout the liquid, not just at the surface.


  13. Give reason: Evaporation is a surface phenomenon.
     Answer: Because only the particles at the surface gain enough energy to escape as vapour.


  14. Give reason: Camphor disappears when kept in open air.
     Answer: Because it undergoes sublimation and changes directly into vapour.


  15. Give reason: LPG is stored under high pressure.
     Answer: Because gases can be liquefied under high pressure and stored in compact form.


  16. Give reason: Ice floats on water.
     Answer: Because ice is less dense than water.


  17. Give reason: The shape of solids is fixed.
     Answer: Because particles in solids are held in fixed positions due to strong intermolecular forces.


  18. Give reason: Gases fill the entire container.
     Answer: Because their particles move freely in all directions due to weak intermolecular forces.


  19. Give reason: Gases exert pressure.
     Answer: Because their particles collide with the walls of the container.


  20. Give reason: Liquids have a definite volume.
     Answer: Because their particles are held by moderate intermolecular forces that restrict their expansion.


  21. Give reason: Water exists in all three states in nature.
     Answer: Because under different temperature and pressure, water can exist as ice (solid), liquid water, and steam (gas).


  22. Give reason: Water vaporises at room temperature.
     Answer: Because some surface particles gain sufficient energy to escape into the air.


  23. Give reason: Melting and freezing occur at the same temperature.
     Answer: Because both involve phase change between solid and liquid at equilibrium conditions.


  24. Give reason: Evaporation causes cooling.
     Answer: Because particles take away heat energy from the surface while escaping.


  25. Give reason: Water condenses on the outer surface of a cold glass.
     Answer: Because water vapour from the air cools and changes into liquid.


  26. Give reason: Mass remains constant during physical changes.
     Answer: Because no new substance is formed and matter is neither created nor destroyed.


  27. Give reason: Ice melts faster in summer than in winter.
     Answer: Because the higher temperature increases the kinetic energy of the particles.


  28. Give reason: Gases are stored in cylinders under high pressure.
     Answer: Because high pressure compresses the gas, reducing its volume for storage.


  29. Give reason: Solids are rigid.
     Answer: Because their particles are fixed and cannot move freely.


  30. Give reason: Boiling water remains at 100°C until all water turns into steam.
     Answer: Because the supplied heat is used in changing state (latent heat), not raising temperature.


  31. Give reason: Naphthalene balls disappear over time.
     Answer: Because they undergo sublimation.


  32. Give reason: Landolt’s experiment is used in chemical reactions.
     Answer: Because it proves the Law of Conservation of Mass by showing that mass remains unchanged.


  33. Give reason: Steam at 100°C is more harmful than water at 100°C.
     Answer: Because steam contains additional energy in the form of latent heat.


  34. Give reason: Intermolecular force affects the state of matter.
     Answer: Because stronger forces result in solids, moderate in liquids, and weak in gases.


  35. Give reason: Evaporation increases with wind speed.
     Answer: Because moving air carries away water vapour, increasing evaporation rate.


  36. Give reason: We feel cool after sweating.
     Answer: Because evaporation of sweat absorbs heat from our body.


  37. Give reason: Liquids are less rigid than solids.
     Answer: Because the intermolecular forces are weaker, allowing particles to move.


  38. Give reason: Water forms droplets on a cold surface.
     Answer: Because water vapour condenses when it comes in contact with a cold surface.


  39. Give reason: Ice has a definite volume.
     Answer: Because particles in ice are tightly packed in a fixed arrangement.


  40. Give reason: Matter changes state on heating or cooling.
     Answer: Because heating increases particle motion and cooling decreases it, affecting intermolecular forces.


  41. Give reason: Air is considered matter.
     Answer: Because it has mass and occupies space.


  42. Give reason: Steam is visible but water vapour is not.
     Answer: Because steam contains tiny droplets of water, while water vapour is a true gas.


  43. Give reason: Matter is conserved in a chemical reaction.
     Answer: Because of the Law of Conservation of Mass, total mass remains unchanged.


  44. Give reason: Liquids and gases are called fluids.
     Answer: Because they can flow due to loosely packed particles.


  45. Give reason: Water takes the shape of its container.
     Answer: Because its particles can move and adjust according to the shape.


  46. Give reason: Gases diffuse faster than liquids.
     Answer: Because gas particles move freely with high kinetic energy and large spaces.


  47. Give reason: Liquids are not easily compressible.
     Answer: Because their particles are already close together, leaving little room for compression.


  48. Give reason: Freezing is an exothermic process.
     Answer: Because heat is released when particles come together to form a solid.


  49. Give reason: Boiling occurs at a fixed temperature.
     Answer: Because the vapour pressure of the liquid equals atmospheric pressure at that point.


  50. Give reason: A solid changes into liquid on heating.
     Answer: Because heat increases kinetic energy, weakening intermolecular forces, allowing particles to move freely.

Arrange the Words 

Case Studies

  1. Case Study: Scenario: During the summer, a student observes that the puddles formed by rain disappear after a while, even though no external heat source is applied.

Question: What is the phenomenon taking place in this scenario?

Answer: The phenomenon is evaporation. The water from the puddles is changing into gas at the surface without reaching its boiling point, due to the energy from the surrounding air.

 

  1. Case Study: Scenario: A container of water is placed in a freezer, and after some time, the water solidifies into ice.

Question: What physical change is happening to the water?

Answer: The water is undergoing freezing, changing from a liquid to a solid as the temperature decreases.

 

  1. Case Study: Scenario: A piece of ice placed on a warm surface starts melting and turns into liquid water.

Question: What is the name of the change occurring, and why does this happen?

Answer: This is melting. The ice gains energy from the warm surface, which increases the kinetic energy of its particles, causing them to overcome intermolecular forces and change from solid to liquid.

 

  1. Case Study: Scenario: You place a glass of cold water in a warm room. After some time, water droplets start forming on the outer surface of the glass.

Question: What is the process responsible for the formation of water droplets on the glass?

Answer: This is condensation. The water vapour in the air cools down when it comes in contact with the cold surface of the glass and changes from gas to liquid.

 

  1. Case Study: Scenario: A student heats a solid sample of iodine, and it starts turning directly into purple vapour.

Question: What process is occurring, and why does it happen?

Answer: This is sublimation, where iodine changes directly from a solid to a gas without passing through the liquid state.

 

  1. Case Study: Scenario: A person is walking in a cold climate and notices the formation of frost on their windows.

Question: What physical change is happening to the water vapour in the air?

Answer: The water vapour is undergoing deposition, changing directly from gas to solid on the cold window surface.

 

  1. Case Study: Scenario: A balloon filled with air is left in the sun. After some time, the balloon expands and increases in size.

Question: What happens to the air inside the balloon as the temperature increases?

Answer: The kinetic energy of the particles in the air increases, causing them to move faster and spread out. This leads to the expansion of the balloon.

 

  1. Case Study: Scenario: A student notices that after placing a wet cloth on a table, the water gradually disappears, even without heating.

Question: What is the reason behind this disappearance?

Answer: This is due to evaporation, where the water molecules at the surface gain enough energy to escape into the air.

 

  1. Case Study: Scenario: A student places a metal spoon in a hot cup of tea. The spoon gradually becomes hotter to the touch.

Question: What process is responsible for the transfer of heat to the spoon?

Answer: This is conduction, where heat is transferred through direct contact from the hot liquid to the cooler spoon.

 

  1. Case Study: Scenario: A gas is compressed into a smaller volume inside a piston.

Question: What effect does the compression have on the gas particles?

Answer: Compression reduces the interparticle space, forcing the particles closer together and increasing the gas’s pressure.

 

  1. Case Study: Scenario: You heat a pan of water until it begins to boil and steam is seen rising from the surface.

Question: What is happening to the water molecules when they turn into steam?

Answer: The water molecules gain sufficient energy to overcome the intermolecular forces, turning from liquid to gas during boiling.

 

  1. Case Study: Scenario: A student places a solid camphor block in a dish, and after some time, the block disappears without turning into a liquid.

Question: What process is occurring, and why is this happening?

Answer: The process is sublimation, where camphor changes directly from solid to gas due to its ability to skip the liquid phase.

 

  1. Case Study: Scenario: When a cold glass of water is left in a humid room, water droplets form on the surface of the glass.

Question: Why do these water droplets form on the surface of the glass?

Answer: This is due to condensation, where the water vapour in the air cools down upon contact with the cold surface of the glass and turns back into liquid.

 

  1. Case Study: Scenario: A student heats water on a stove until it begins to boil. The student observes bubbles form in the water and rise to the surface.

Question: What is happening to the particles of water during boiling?

Answer: During boiling, water particles gain enough energy to move rapidly, forming gas bubbles that rise to the surface and escape as steam.

 

  1. Case Study: Scenario: A student places a balloon filled with air in a freezer. After some time, the balloon shrinks.

Question: What is causing the balloon to shrink in size?

Answer: Cooling the air reduces the kinetic energy of its particles, causing them to contract and decrease the volume of the balloon.

 

  1. Case Study: Scenario: A student notices that when a substance like iodine is heated in a beaker, it produces a violet gas.

Question: What process is this, and what does it indicate about the substance?

Answer: This is sublimation, indicating that iodine can change directly from solid to gas without becoming a liquid.

 

  1. Case Study: Scenario: A student sees that an ice cube in a warm room melts and turns into water.

Question: Why does the ice cube melt?

Answer: The heat from the surroundings increases the kinetic energy of the ice particles, causing them to break free from their fixed positions and turn into liquid water.

 

  1. Case Study: Scenario: A student places a pot of water on a stove. After a while, the water begins to boil, and steam rises from the surface.

Question: What change of state is occurring in the water?

Answer: The water is undergoing boiling, changing from liquid to gas due to the heat provided by the stove.

 

  1. Case Study: Scenario: A solid substance such as naphthalene is placed in a warm room, and after a while, it disappears.

Question: What is happening to the substance?

Answer: The substance is undergoing sublimation, where it directly changes from solid to gas without becoming a liquid.

 

  1. Case Study: Scenario: A student places a pan with water on the stove. The water starts heating up and eventually starts forming bubbles at the bottom of the pan.

Question: What is causing the water to form bubbles?

Answer: The water is reaching its boiling point, where the heat causes the formation of gas bubbles, which rise to the surface as steam.

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