3.2 - Internal Energy and Energy Transfers

Question 1

What is the internal energy of a
substance?

Answer 1

● The energy stored by the particles
● The sum of the total kinetic and
potential energies that make up the
system

Question 2

How does heating affect the energy of a
substance?

Answer 2

● Heating transfers energy to the
substance
● It increases the energy of the particles
that make up the substance

Question 3

What two things can heating a substance do?

Answer 3

1. Raise its temperature
2. Change the state of the substance

Question 4

What three factors determine the
temperature change of a system?

Answer 4

1. Mass of substance being heated
2. Type of material (Specific heat
   capacity)
3. Energy inputted into the system

Question 5

Define specific heat capacity.

Answer 5

The amount of energy needed to
increase the temperature of 1kg of a substance by 1°C.

Question 6

Describe how the internal energy and
temperature of a substance changes
when a change of state occurs.

Answer 6

● The internal energy of the substance
will be increased or decreased
● The temperature of the substance will
remain constant

Question 7

Define specific latent heat.

Answer 7

The amount of energy needed to change
the state of 1kg of a substance with no
change in temperature.

Question 8

What is the specific latent heat of fusion?

Answer 8

The energy required to change 1kg of a
substance from solid state to liquid state
without a change in temperature.

Question 9

What is the specific latent heat of
vaporisation?

Answer 9

The energy required to change 1kg of a
substance from liquid state to gas state
(vapour) without a change in
temperature.

Question 10

Why doesnt the temperature change

Answer 10

the heat energy produced is used up in changing the state of matter and also for breaking numerous bonds or attractive forces