Gas particles move in random directions. This means that they collide with each other and with the container they are in. | Gas Particle Movement |
How do gas particles move? | In random directions, colliding with each other and with the container. |
The force created by these collisions is at right angles to the wall of the container. | Collision Force Direction |
In what direction is the force created by gas particle collisions relative to the container wall? | At right angles to the wall of the container. |
When the pressure of a gas changes, it can take up more space (expand) or less space (compress). | Pressure Change and Volume |
What happens to the volume of a gas when its pressure changes? | It can expand (take up more space) or compress (take up less space). |
Increasing the pressure of a gas increases the force exerted on the wall of the container. If the gas is in a stretchy container like a balloon, this may cause the container to expand. | Increasing Pressure |
What effect does increasing the pressure of a gas have on a stretchy container like a balloon? | It may cause the container to expand. |
Decreasing the pressure of a gas decreases the force exerted on the wall of the container. | Decreasing Pressure |
What effect does decreasing the pressure of a gas have on the force exerted on the container wall? | It decreases the force exerted on the wall. |
The gas outside the container also exerts a force on the container. As a result, the container may be compressed by the pressure of the gas outside the container. | External Pressure on Container |
How does external pressure affect a gas container? | The container may be compressed by the pressure of the gas outside the container. |
If temperature is kept constant, increasing the volume of the container a gas is in gives the particles more room to spread out. | Volume Increase and Gas Pressure |
What happens to gas particles when the volume of their container is increased, assuming temperature is constant? | The particles have more room to spread out. |
Because the gas particles spread out, there are fewer collisions with the walls of the container. As a result, the pressure exerted by a fixed mass of the gas will decrease. | Effect of Spreading Out Particles |
Why does the pressure exerted by a gas decrease when the volume of its container is increased? | There are fewer collisions with the walls of the container as the particles spread out. |
If temperature is kept constant, decreasing the volume of a gas gives particles less room to move. | Volume Decrease and Gas Pressure |
What happens to gas particles when the volume of their container is decreased, assuming temperature is constant? | The particles have less room to move. |
This means the particles collide more often with the container walls. As a result, the pressure exerted by the gas will increase. | Effect of Constrained Particles |
Why does the pressure exerted by a gas increase when the volume of its container is decreased? | The particles collide more often with the container walls. |
Pressure and volume are inversely proportional. | Inverse Proportionality of Pressure and Volume |
What is the relationship between pressure and volume in a gas? | They are inversely proportional. |
When the volume of a gas increases, the pressure decreases. | Volume Increase and Pressure Decrease |
What happens to the pressure when the volume of a gas increases? | The pressure decreases. |
When the volume of a gas decreases, the pressure increases. | Volume Decrease and Pressure Increase |
What happens to the pressure when the volume of a gas decreases? | The pressure increases. |
For a fixed mass of gas at a constant temperature we can use this equation: | Pressure-Volume Equation |
For example, a gas has a volume of 400 m³ and exerts a pressure of 50 Pa. What is the pressure exerted if it is compressed to 100 m³? First, plug the values into the equation: | Example Calculation Setup |
Then we can rearrange the equation to solve for pressure: | Solving for New Pressure |
What is the new pressure exerted after the gas is compressed to 100 m³? | The new pressure (P2) is 200 Pa. |
Increasing the pressure of a gas increases its temperature. | Pressure Increase and Temperature |
What happens to the temperature of a gas when its pressure is increased? | The temperature increases. |
When you apply a force, work is done. | Work and Force |
What is done when you apply a force? | Work is done. |
Work is the transfer of energy. | Definition of Work |
What is the definition of work? | Work is the transfer of energy. |
When work is done on a gas, energy is transferred to the kinetic energy store of the gas particles. This increases the internal energy of the gas. | Work Done on Gas |
What happens when work is done on a gas? | Energy is transferred to the kinetic energy store of the gas particles, increasing the internal energy of the gas. |
An increase in internal energy increases the temperature. | Internal Energy and Temperature |
How does an increase in internal energy affect the temperature of a gas? | It increases the temperature. |
For example, the force provided by a bicycle pump increases the pressure of air in the tyres. The work done on the gas makes the tyre feel hotter. | Example of Work Done on Gas |
How does the work done by a bicycle pump affect the air in the tyres? | It increases the pressure and makes the tyre feel hotter due to the increase in temperature. |