Particle Model & Pressure Practice Questions

The temperature of the gas is $45\ \degree\text{C}$.

Convert this temperature to kelvin.

temperature = ............................................... K

The container is then cooled until the gas is at a temperature of $195$ K.

Convert this temperature to degrees Celsius.

temperature = ............................................... $\degree\text{C}$

A student says, 'If you keep cooling the gas, the particles just keep getting slower and slower for ever.'

Explain why the student is wrong.

A sealed metal can with rigid walls contains air. The can is heated from $20\ \degree\text{C}$ to $80\ \degree\text{C}$.

Which of these is correct?

A The mass of the air inside the can decreases.

B The average speed of the air particles decreases.

C The air particles hit the walls of the can more often.

D The volume of the air inside the can increases greatly.

Explain, in terms of the movement of the air particles, how the trapped air produces a pressure on the inside of the lid.

State the direction of the force that the trapped air exerts on the flat lid.

Calculate the volume of the gas inside the balloon at this height.

Use an equation selected from the list of equations at the end of this paper.

volume = ............................................... $\text{m}^3$

Explain, in terms of the gas particles, why the gas inside the balloon expands as the balloon rises.

Explain why the temperature of the air inside the tube increases when the piston is pushed down quickly.

A student tries to use the equation $P_1 \times V_1 = P_2 \times V_2$ to calculate the pressure of the air in the tube at the end of the compression.

Explain why the student's calculated value will be too low.

Convert both of these temperatures to the kelvin scale.

$12\ \degree\text{C}$ = ............................................... K

$45\ \degree\text{C}$ = ............................................... K

Explain, in terms of the particles of the gas, why the pressure of the air inside the cylinder increases as it warms up.

Use the results in the table to calculate the missing value of the pressure.

pressure = ............................................... kPa

Explain, in terms of the air particles, why the pressure increases as the volume of the trapped air is decreased.

State why the student pushes the plunger in slowly.

Calculate the total volume that the helium in the full cylinder would occupy at a pressure of $1.1 \times 10^5$ Pa.

Use an equation selected from the list of equations at the end of this paper.

volume = ............................................... $\text{m}^3$

Gas can only be released from the cylinder until the pressure inside it has fallen to $1.1 \times 10^5$ Pa.

Calculate the maximum number of balloons that can be filled from this cylinder.

number of balloons = ...............................................