Specific Heat Capacity

Question 1

True or false? If a material has a high specific heat capacity, a relatively large amount of energy is required to increase its temperature by a certain amount.

Answer 1

True

Specific heat capacity is the energy required to raise the temperature of 1kg of a substance by 1°C

Question 2

What does the ∆ symbol mean?

Answer 2

The symbol ∆ means “change in”.

Question 3

The specific heat capacity of iron is 450 J/kg°C.
How much energy will have been transferred to a 0.5kg iron block if its temperature rises by 10°C?
(Change in thermal energy = mass x specific heat capacity x change in temperature)

Answer 3

2250J

∆Q = m x c x ∆θ = 0.5 x 450 x 10 = 2250J

Question 4

Dan carries out an experiment to measure the specific heat capacity of milk. He uses an electric heater to heat 200g of milk in a container. How can Dan make sure that as much energy as possible is transferred by the heater to the milk?

Answer 4

Dan can thermally insulate the container and put a lid on it before he starts heating the milk, to reduce the amount of energy wastefully transferred to the surroundings.

Question 5

In Dan’s experiment, 8000J of energy was transferred to the milk to raise its temperature by 10°C. Use these results to calculate the specific heat capacity of milk

Answer 5

4000 J/kg°C

∆Q = m x c x ∆θ so c = ∆Q/m x ∆θ  
m = 200 g = 0.2 kg

c = 8000/0.2 x 10 = 8000/2 = 4000J/kg°C