Pre AP Chemistry -1.3A Gas Pressure and Particle Collisions- MCQ Exam Style Questions -New Syllabus 2025-2026
Pre AP Chemistry -1.3A Gas Pressure and Particle Collisions- MCQ Exam Style Questions – New Syllabus 2025-2026
Pre AP Chemistry -1.3A Gas Pressure and Particle Collisions- MCQ Exam Style Questions – Pre AP Chemistry – per latest Pre AP Chemistry Syllabus.
Questions
Which statement describes what happens as ice at 0 \(\circ \) C melts to become water?
A Energy is absorbed and the temperature remains constant.
B Energy is absorbed and the temperature rises.
C Energy is released and the temperature remains constant.
D Energy is released and the temperature rises
▶️Answer/Explanation
Ans A
Questions
Brownian motion of particles is observed. Which statements describe the movement of the particles?
1 The particles all travel along a curved path.
2 The particles move randomly.
3 The particles all travel in the same direction.
A 1 and 3
B 1 only
C 2 and 3
D 2 only
▶️Answer/Explanation
Ans D
Questions
A piece of solid metal melts to become a liquid. How do the particles of metal or their behaviour change?
A They increase in size.
B They move around each other.
C They move much further apart.
D They vibrate more about their fixed positions.
▶️Answer/Explanation
Ans B
Question
Smoke particles, illuminated by a bright lamp, are seen through a microscope. They move about randomly.
What causes this motion?
- attraction between the smoke particles and the molecules of the air
- collisions between the smoke particles and the molecules of the air
- evaporation of the faster-moving smoke particles
- warming of the smoke particles by the lamp
Answer/Explanation
Ans:
B
Question
What is a basic assumption of the kinetic theory, as applied to an ideal gas?
A Collisions between gas molecules are elastic.
B Each gas molecule occupies a finite volume.
C Gases consist of particles that experience the force of gravity.
D Gas molecules attract each other with weak intermolecular forces.
Answer/Explanation
Answer A
Question
In an experiment, smoke particles are suspended in air and viewed through a microscope.
The smoke particles move about with short random movements. Which of the following statements is correct?
A Air particles have large masses compared to smoke particles and they move in one directiononly.
B Air particles have large masses compared to smoke particles and they move in random directions.
C Air particles move at high speeds compared to smoke particles and they move in one direction only.
D Air particles move at high speeds compared to smoke particles and they move in random directions.
Answer/Explanation
Ans: D
Question
Which row describes the forces between the molecules and the motion of the molecules in a gas?
| forces between molecules | motion of molecules |
A | strong | move freely |
B | strong | vibrate only |
C | weak | move freely |
D | weak | vibrate only |
Answer/Explanation
Ans: C
Question
A gas is heated in a sealed container.
The volume of the container does not change.
What happens to the molecules of the gas?
The average distance between molecules increases.
The average kinetic energy of the molecules increases.
The mass of each molecule increases.
The volume of each molecule increases.
Answer/Explanation
Ans: B
Question
A stationary smoke particle is hit by a fast-moving nitrogen molecule.
Which row describes the motion of the smoke particle and of the nitrogen molecule after
the collision?
| smoke particle | nitrogen molecule |
A | moves | rebounds |
B | moves | stops |
C | remains stationary | rebounds |
D | remains stationary | stops |
Answer/Explanation
Ans: A
Question
Brownian motion is observed when looking at smoke particles in air using a microscope.
What causes the smoke particles to move at random?
A. Smoke particles are hit by air molecules.
B. Smoke particles are moved by convection currents in the air.
C. Smoke particles have different weights and fall at different speeds.
D. Smoke particles hit the walls of the container.
Answer/Explanation
Ans: A
Question
The molecules of a substance become more closely packed and move more quickly.
What is happening to the substance?
A A gas is being heated and compressed.
B A gas is being heated and is expanding.
C A liquid is boiling.
D A liquid is evaporating at room temperature.
Answer/Explanation
Ans: A
Question
Brownian motion is observed when using a microscope to look at smoke particles in air.
What causes the smoke particles to move at random?
A. Smoke particles are hit by air molecules.
B. Smoke particles are moved by convection currents in the air.
C. Smoke particles have different weights and fall at different speeds.
D. Smoke particles hit the walls of the container.
Answer/Explanation
Ans: A
Question
The diagram shows a sealed jar containing a gas.
Which statement about the gas in the jar is correct?
A. The gas molecules collide with the inside of the jar more often as the temperature increases.
B. The gas molecules move more slowly as the temperature increases.
C. The pressure of the gas decreases as the temperature increases.
D. The pressure of the gas is higher at the top of the jar than at the bottom of the jar.
Answer/Explanation
Ans: A
Question
A student places his thumb firmly on the outlet of a bicycle pump, to stop the air coming out.
What happens to the pressure and what happens to the volume of the trapped air as the pump handle is pushed in?
| pressure | volume |
A | decreases | decreases |
B | decreases | remains the same |
C | increases | decreases |
D | increases | remains the same |
Answer/Explanation
Ans: C
Question
A gas is stored in a sealed container of constant volume. The temperature of the gas increases.
This causes the pressure of the gas to increase.
What happens to the gas molecules during this pressure increase?
The average kinetic energy of the molecules increases.
The average separation of the molecules decreases.
The average separation of the molecules increases.
The volume of each molecule increases.
Answer/Explanation
Ans: A
Question
Extremely small pollen grains in water are viewed through a microscope. The grains are seen to move continually and randomly.
What is the reason for this random movement?
The grains are moved by randomly moving water molecules.
The grains are moved by random convection currents in the water.
The grains are moved by random rays of light reflecting off them.
The grains are moved by the random motion of their own atoms.
Answer/Explanation
Ans: A
Question
When a microscope is used to look at smoke particles in air, Brownian motion is observed.
What causes the smoke particles to move at random?
A Smoke particles are hit by air molecules.
B Smoke particles are moved by convection currents in the air.
C Smoke particles have different weights and fall at different speeds.
D Smoke particles hit the walls of the container.
Answer/Explanation
Ans: A