Particle motion In Gases

Question 1

A particle model…

Answer 1

Helps explain how temperature and pressure and volume and energy in kinetic stores are all related

Question 2

The particles in a gas are…

Answer 2

Are constantly moving with random directions and speeds

Question 3

If you increase the temperature of a gas

Answer 3

You transfer energy into the kinetic energy stores of its particles

Question 4

The temperature of a gas is related to the

Answer 4

Average energy in the kinetic energy stores of the particles in a gas.

Question 5

The higher the temperature

Answer 5

The higher the average energy

Question 6

So as you increase the temperature of the gas

Answer 6

Average speed of its particles increases. This is because the energy in the particles kinetic energy stores is 1/2 MV squared-

Question 7

As gas particles move about at high speeds

Answer 7

They bang into each other and whatever else happens to get in the way

Question 8

When gases collide with something

Answer 8

They exert a force and so pressure on it

Question 9

In a sealed container

Answer 9

The outward gas pressure is the total force exerted by all of the particles in the gas on a unit area of the container walls.

Question 10

Faster particles and more frequent collisions both lead to an

Answer 10

Increase in net force and so gas pressure

Question 11

Increasing the temperature will increase the speed

Answer 11

And so the pressure volume is kept constant

Question 12

Alternatively, if temperature is constant

Answer 12

Increasing the volume of a gas means the particles get more spread out and hit the walls of the container less often. The gas pressure decreases.

Question 13

Pressure and volume inversely portional when volume goes up

Answer 13

Pressure goes down

Question 14

What is the formula for a glass of fixed mass at a constant temperature

Answer 14

PV equals constant (pressure in pascals (Pa)

V = volume (m3)

Question 15

The pressure of a gas causes…

Answer 15

A net outwards force at right angles to the surface of its container

Question 16

There is also a force in the

Answer 16

Outside of the outside of the container due to the pressure of the gas around it

Question 17

If the container can easily change it size

Answer 17

Then any change in these pressures will cause the container to compress or expand, due to the overall force

Question 18

If you transfer energy by applying a force

Answer 18

Then you do work

Question 19

Doing work on a gas increases internal energy

Answer 19

Which can increase its temperature

Question 20

You can do work in a gas

Answer 20

Mechanically (eg with a bike pump)

Question 21

The gas applied pressure to the plunger of the pump

Answer 21

And exerts a force on it

Question 22

Work has to be done against a force

Answer 22

To push down on something

Question 23

This transfers energy to the

Answer 23

Kinetic energy of the gas particles increasing the temperature