Chapter #10 - Thermal Properties of Matter

Question 1

What is thermal expansion?

Answer 1

The increase in volume of a material when its temp. rises.

Question 2

How are railways protected form bending?

Answer 2

By being built in sections with expansion joints.

Question 3

What is the internal energy of a substance made of?

Answer 3

Internal energy is made of kinetic energy of particles and the chemical potential energy of the bonds between them.

Question 4

How do you increase the kinetic energy of particles?

Answer 4

By applying thermal energy.

Question 5

What is the defenitionf of specific heat capacity?

Answer 5

The energy needed to raise the temp. of 1kg of substances by 1 celcius.

Question 6

What happens to the force with whatch gasses collide as the temp. rises.

Answer 6

They collide with more force, they expand.

Question 7

What is the order of expansion with states of matter?

Most to least expanded

Answer 7

1. gases
2. liquids
3. solids

Question 8

What happens to the space particles take as they gain energy?

Answer 8

They move arround more and take up more space.

Question 9

What factors which apply for how much energy we need to boil water?

Answer 9

• The mass of the water.
• The increase in temperature.

Question 10

How much energy does it take to raise the temp. of 1kg of water by one celcius?

Answer 10

4200J / Kg celcius

Question 11

What are the concequences of water having a pretty high specific heat capacity compared to other substances?

Answer 11

• It takes a lot of energy to heat up with water
• Hot water takes a long time to cool down

Question 12

What changes the bpt. and freexing point of water?

Answer 12

Dissolving substaces in it.

Question 13

How does salt change the bpt. of water?

Answer 13

It boils at a higer temp.

Question 14

How does water evaporate?

Answer 14

1. The particles on the surface of the water are moving.
2. Some are moving faster (have more energy)
3. Some move faste enough to escape from the surface of the water.
4. They become water vapour particles.

Question 15

How does evaporation cool our body and why does this happen?

Answer 15

If you get wet, you will quickley get cold , because the H2O in your body is evaporating this is because:
* Particles of highe kinetic energy have left your body
* Particles that remain have less kinetic energy
* Now, particles of liquid have less kinetic energy, so liquid cools down*

Question 16

What temp. does evaporation and boiling happen at?

Answer 16

Evaporation: All temperatures
Boiling: At the substances boiling point.

Question 17

What part of the liquid does evaporation and boiling happen at?

Answer 17

Evaporation: At the surface
Boiling: Throughout the liquid

Question 18

What are the ways to speed up evaporation?

Answer 18

• Increasing the temperature
• Increasing the surface area
• Blowing air across the surface