P3- Particle Model Of Matter

Question 1

What are the 3 states of matter?

Answer 1

Solid
Liquid
Gas

Question 2

How are particles arranged in a solid?

Answer 2

1. Particles are held close together by strong forces in a regular, fixed pattern.
2. The particles don’t have much energy.
3. So they only vibrate around a fixed position.

Question 3

How are particles arranged in a liquid?

Answer 3

1. The particles are held close together in an irregular pattern.
2. The particles have more energy than the particles in a solid.
3. They can move past each other in random directions at low speeds.

Question 4

How are particles arranged in a gas?

Answer 4

1. The particles aren’t held close together. There are no forced between them.
2. The particles have more energy than in liquids and solids.
3. The particles constantly move around in random directions at a range of speeds.
4. They are free to move around
5. They collide with each other and the sides of the container they are in.
6. When they hit something, they apply a force to it.
7. Pressure is the force applied over a given area.
   (Gas particles bump into things and create pressure)

Question 5

When you increase the temperature of a gas what does it increase?

Answer 5

When you increase the temperature of a gas, the gas increases its pressure.

Question 6

How does temperature control gas.

Answer 6

1. The temperature of the gas depends on the average energy in the kinetic energy store in the has particles
2. The hotter the gas, the higher the average energy.
3. If particles have more energy in their kinetic stores, they move faster.
4. So the higher the gas, the faster the particles move on average.
5. Faster particles hit the sides of the container more often.
6. This increases the force in the container.
7. So increasing the temperature of a gas increases it’s pressure.
8. This only works if the space the gas takes up (the volume) doesn’t change.

Question 7

What is the measure density practical?

Question 8

What is internal energy?

Answer 8

Internal energy is the total energy stored by particles in a system.

Question 9

What increases the internal energy?

Answer 9

Heat.

Question 10

How does heat increase the internal energy?

Answer 10

1. Heating a system transfers energy to its particles.
2. This increases the systems internal energy.
3. This leads to a change in temperature or a change in state (e.g melting or boiling)
4. How much the temperature changes depends on the mass of the system, it’s specific heat capacity and how much energy is transferred to it
5. A change of state happens when the particles have enough energy un their kinetic energy stored to break the bonds holding them together.

Question 11

From solid to liquid what is the change of state?

Answer 11

Melting.

Question 12

From liquid to gas what is the change of state?

Answer 12

Boiling/ evaporating

Question 13

From liquid to solid what is the change of state?

Answer 13

Freezing

Question 14

From gas to liquid what is the change of state?

Answer 14

Condensing

Question 15

From solid straight to gas what is the change of state?

Answer 15

Sublimating

Question 16

Is a change of state a physical or chemical change?

Answer 16

Physical
- this means you don’t end up with new material (the particles are just arranged in a different way)

Question 17

Does the number of particles change stay the same or change when the state changes?

Answer 17

1. The number of particles stay the same when the state changes.
2. This means that the mass is conserved ( it doesn’t change)

Question 18

What does heating a material transfer?

Answer 18

Energy to the material.

Question 19

When you heat a material, what happens?

Answer 19

1. Heating a material transfers energy to the material.
2. This either increases the temperature of the material or changes it’s state.
3. During a change of state the temperature doesn’t change, but the internal energy does.
4. The energy transferred is used to break bonds between particles.
   ( it is NOT used to raise temperature)
5. When a material condensed or freezes bonds form between particles.
6. This cases energy to be released.
7. So it’s internal energy decreases, but it’s temperature stays the same during the change of state.

Question 20

What is specific latent heat?

Answer 20

Specific latent heat is the energy needed to change the state of a 1kg mass without changing its temperature.

Question 21

What is the energy transferred during a change in state called?

Answer 21

Latent heat.

Question 22

For heating, latent heat does what?

Answer 22

For heating, latent heat is the energy gained to cause a change of state.

Question 23

For cooling, latent heat is what?

Answer 23

For cooling, latent heat is the energy released by a change in state.

Question 24

What’s the difference between specific latent heat and specific heat capacity?

Answer 24

1. Specific latent heat is about the change in state.
2. Specific heat capacity is to do with changes in temperature.

Question 25

What is the formula to work out the energy needed (or released) during a change of state?

Answer 25

Energy = mass x specific latent heat

E= mL