K.C.S.E Physics Q & A - MODEL 2016PP1QN15

K.C.S.E Physics Q & A - MODEL 2016PP1QN15

​(a) State what is meant by an ideal gas 
(b) The pressure acting on a gas in a container was changed steadily while the temperature of the gas maintained constant. The value of volume V of the gas was measured for various values of pressure. The graph in figure 11 shows the relation between the pressure, p and the reciprocal of volume 1/v

(i) Suggest how the temperature of the gas could be kept constant
(ii) Given that the relation between the pressure P1 and the volume, V₁ of the gas is given by PV = k, where k is a constant, use the graph to determine the value of k.
(iii) What physical quantity does k represent?
(iv)State one precaution you would take when performing such an experiment
(c) A gas occupies a volume of 4000 litres at a temperature of 37⁰C and normal atmospheric pressure. Determine the new volume of the gas if it is heated at constant pressure to a temperature of 67⁰C (normal atmospheric pressure P= 1.01 x 10⁵ pa)

answers

​(a)A gas that obeys the gas laws perfectly
(b) (i)By changing pressure very slowly or by allowing gas to go to original temperature after each change

​(iii)Work done on the gas
(iv)Use dry gas
Make very small changes in pressure