Specific Heat Capacity and Latent Heat Questions - GCSE standard

Q14.

Bill performs an experiment to find the specific heat capacity of water.

He heats up 1kg of water, using an immersion heater.

He measures the temperature rise and calculates the specific heat capacity of the water.

Attempt
Energy supplied /J
Temperature rise /°C
Specific heat capacity in J/kg°C
1
10000
2
5000
2
21000
4
5250
3
44000
8
5500

 

(a)

(i) Calculate the mean specific heat capacity.

5000 + 5250 + 5500 = 15750

Mean value = 15750/3 = 15250 J/kgoC

[1 mark]

(ii) Describe the conclusions that can be drawn from the data.

This is a foundation level paper - so all sorts of interpretations of the data got you a mark!

Any three from:

s.h.c. increases with longer heating

specific heat capacity increases with temperature rise

specific heat capacity increases with energy supplied

temperature rise increases with energy supplied

different amounts of energy were supplied

all of the s.h.cs. are close together (within 5%)

all of the s.h.c values are within the range 5000 – 5500 J/kgoC

the experiment was repeated three times

[3 marks]

(b) The actual value for the specific heat capacity of water is 4200J/kg°C.

(i) Explain why the mean specific heat capacity calculated in (a)(i) is higher than the actual value.

Becuse more energy was recorded as having heated the water than actually did so, because energy losses occurred as energy was transferred to the environment.

[2 marks]

(ii) Identify two problems with this experimental procedure and suggest how each one could be solved.

Any two linked answers from:

Part of the immersion heater is out of the waterso make sure the heater is fully in the water or use a larger/deeper beaker.

The beaker is not lagged/insulated so lag/insulate the beaker.

There is no lid on the beaker put a lid on the beaker

The temperature rises are quite small apply more energy to the water

There is insufficient data so take more readings

[4 marks]

(10 marks total)