Kinetic Particle Model of MatterCopy
- Which of the following best explains why gas molecules exert pressure on the walls of a container? A. Due to gravitational potential energy
B. Due to collisions of molecules with container walls
C. Because of intermolecular attractions
D. Because energy is lost during collisions - Which state of matter has the highest average kinetic energy at a fixed temperature? A. Solid
B. Liquid
C. Gas
D. Plasma - Which process involves a change of state without a temperature change? A. Heating a solid
B. Cooling a gas
C. Melting
D. Heating a liquid - In the kinetic particle model, why does a solid have a fixed shape? A. Particles are stationary
B. Particles can only rotate
C. Particles are in a fixed, vibrational position
D. Particles flow in layers - Which of the following correctly ranks the strength of intermolecular forces from greatest to least? A. Gas > Liquid > Solid
B. Solid > Gas > Liquid
C. Liquid > Solid > Gas
D. Solid > Liquid > Gas - The Brownian motion observed in smoke particles is evidence that: A. Air is a vacuum
B. Particles are held together by strong forces
C. Air molecules move randomly
D. Gas particles settle due to gravity - Which of the following would most likely cause an increase in the pressure of a gas in a sealed container? A. Decreasing temperature
B. Decreasing volume
C. Decreasing the number of molecules
D. Increasing the size of the container - During evaporation, the molecules that escape from the liquid are those that: A. Have the lowest energy
B. Are at the bottom of the liquid
C. Have the highest energy
D. Are bonded with impurities - The melting point of a substance is defined as: A. The temperature at which all particles stop moving
B. The temperature at which a solid becomes a liquid
C. The point when temperature is constant in a gas
D. The average kinetic energy of gas molecules - In a solid, the kinetic energy of the particles: A. Is constant throughout
B. Is zero due to no movement
C. Increases with temperature
D. Decreases with increased pressure - Which of the following is NOT an assumption of the kinetic particle model? A. Particles are in constant motion
B. Intermolecular forces are significant in gases
C. Collisions between particles are elastic
D. Particle movement increases with temperature - Which statement best describes sublimation? A. A solid becomes a liquid then a gas
B. A liquid becomes a gas
C. A gas becomes a solid
D. A solid changes directly to a gas - The boiling point of a liquid depends on: A. The size of the container
B. The mass of the liquid
C. Atmospheric pressure
D. The time of heating - Which of the following will increase the rate of diffusion of a gas? A. Lower temperature
B. Higher molecular mass
C. Smaller volume
D. Higher temperature - Why does a balloon expand when heated? A. The balloon material weakens
B. Gas molecules combine
C. The gas molecules move faster and collide more
D. Heat causes particles to evaporate - Which of the following provides the best evidence for the existence of atoms? A. Boiling water
B. Melting ice
C. Brownian motion
D. Freezing ethanol - During the process of condensation, the internal energy of a substance: A. Increases
B. Decreases
C. Remains constant
D. Is converted entirely into kinetic energy - The kinetic theory fails to explain: A. Gas pressure
B. Solid’s fixed volume
C. Surface tension
D. Particle vibration - Which of the following changes of state is endothermic? A. Freezing
B. Condensation
C. Melting
D. Deposition - In the gaseous state, the volume of a substance is mainly due to: A. The volume of the particles
B. The arrangement of molecules
C. The space between particles
D. The mass of the molecules - When a substance sublimes, what must be true? A. The pressure is higher than atmospheric
B. The temperature is above the boiling point
C. The substance skips the liquid phase
D. The molecular mass is very low - When a liquid boils, its temperature: A. Increases rapidly
B. Remains constant
C. Decreases slightly
D. Rises and falls alternately - Why are gases compressible but solids are not? A. Solids have more energy
B. Gases have intermolecular forces
C. There is more empty space between gas molecules
D. Solids lack kinetic energy - Which state of matter is the best conductor of heat? A. Gas
B. Plasma
C. Solid
D. Liquid - What is the effect of pressure on boiling point? A. No effect
B. Increases it
C. Decreases it
D. Removes it - Particles in a liquid differ from those in a gas because: A. They move slower
B. They do not vibrate
C. They are fixed
D. They attract only when cooled - A substance with strong intermolecular forces will likely: A. Sublime easily
B. Boil at low temperature
C. Be a gas at room temperature
D. Have a high boiling point - In gases, the average speed of particles is dependent on: A. Pressure
B. Temperature
C. Mass of container
D. Density - An increase in temperature results in: A. Decreased kinetic energy
B. Constant motion
C. Increased vibration in solids
D. Increase in intermolecular force - Why does solid iodine appear to ‘disappear’ at room temperature? A. It melts then evaporates
B. It sublimes
C. It reacts with air
D. It is radioactive - If two gases have the same temperature, which has the faster average speed? A. The one with lower molecular mass
B. The heavier one
C. Both are equal
D. Cannot be determined - Gases do not settle because: A. Gravity acts upwards
B. Their particles vibrate
C. They move in random motion
D. They attract each other - The reason liquids take the shape of a container is because: A. Particles are tightly packed
B. Particles vibrate only
C. Particles slide past each other
D. Liquids have no particles - Which state of matter allows flow but is not easily compressed? A. Solid
B. Liquid
C. Gas
D. Plasma - Why does evaporation cause cooling? A. Molecules collide with surrounding air
B. Particles vibrate more
C. Only low-energy particles leave
D. High-energy particles escape, reducing average energy
Written and Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Physics Full Scale Course
Answer Key & Explanations
| Q# | Ans | Explanation |
|---|---|---|
| 1 | B | Collisions with the walls cause force, resulting in pressure. |
| 2 | C | Gas particles have the most kinetic energy at a given temperature. |
| 3 | C | Melting is a phase change; temperature remains constant. |
| 4 | C | In solids, particles vibrate about fixed positions. |
| 5 | D | Solids have the strongest forces, gases the weakest. |
| 6 | C | Brownian motion is due to collisions by moving air molecules. |
| 7 | B | Decreasing volume increases frequency of collisions, raising pressure. |
| 8 | C | Molecules with highest energy escape first during evaporation. |
| 9 | B | Defined as temperature where solid turns to liquid. |
| 10 | C | Increasing temperature raises particle kinetic energy. |
| 11 | B | In gases, intermolecular forces are negligible, not significant. |
| 12 | D | Sublimation is direct solid-to-gas transition. |
| 13 | C | Boiling point increases with atmospheric pressure. |
| 14 | D | Higher temperature increases molecular speed and diffusion. |
| 15 | C | Molecules move faster with heat, colliding more with the walls. |
| 16 | C | Brownian motion reveals air molecules in random motion. |
| 17 | B | Heat is released, so internal energy decreases. |
| 18 | C | Surface tension is not well explained by kinetic theory. |
| 19 | C | Melting requires energy input = endothermic. |
| 20 | C | Gas particles are far apart; most volume is empty space. |
| 21 | C | Sublimation skips the liquid phase. |
| 22 | B | During boiling, energy goes into breaking bonds, not raising temp. |
| 23 | C | Gases have space between particles; solids do not. |
| 24 | C | Solids conduct best due to closely packed particles. |
| 25 | B | Boiling point increases with pressure. |
| 26 | A | Liquid particles move slower than gas particles. |
| 27 | D | Strong forces = more energy needed = higher boiling point. |
| 28 | B | Temperature controls particle speed in gases. |
| 29 | C | Higher temperature increases vibration in solids. |
| 30 | B | Iodine sublimes at room temperature. |
| 31 | A | Lighter particles move faster at same kinetic energy. |
| 32 | C | Gases move randomly, preventing settling. |
| 33 | C | Liquid particles slide past each other, allowing shape change. |
| 34 | B | Liquids flow but cannot be compressed easily. |
| 35 | D | Fast-moving particles leave, lowering average energy, thus cooling. |
Written and Compiled By Sir Hunain Zia, World Record Holder With 154 Total A Grades, 7 Distinctions and 11 World Records For Educate A Change O Level And IGCSE Physics Full Scale Course