A level: Kinetic Theory Questions

Q17. A number of assumptions are made when explaining the behaviour of a gas using the molecular kinetic theory model.

(a) State one assumption about the size of molecules.

[1 mark]

(b) The graph shows how the pressure changes with volume for a fixed mass of an ideal gas.

At A the temperature of the gas is 27 ^oC.

The gas then undergoes two changes, one from A to B and then one from B to C.

(i) Calculate the number of gas molecules trapped in the cylinder using information from the initial situation at A.

[2 marks]

(ii) Calculate, in K, the change in temperature of the gas during the compression that occurs between A and B.

[2 marks]

(iii) Deduce whether the temperature of the gas changes during the compression of the gas from B to C.

[2 marks]

(iv) Compare the work done on the gas during the change from A to B with that from B to C.

[3 marks]

(10 marks total)