A gas at a pressure of 2 bar occupies a volume of 0.2 m3.If the temperature of the gas is 25C and the characteristic constant for the gas is 0.35 kJ kg-1K-1, calculate :

(a)the mass of the gas

(b)the pressure of the gas after it is compressed isothermally to half of its original volume.

(c) 0.5 kg of a gas is held in a rigid container of volume 0.25 m3at a temperature of 20C.20 kJ of heat energy is required to increase the temperature of the gas to 60C.

When the same mass of gas is heated at constant pressure, 30 kJ of heat energy is required to create the same temperature rise. Calculate:

(i)the specific heat capacities of the gas at constant volume and constant pressure

(ii)the initial pressure of the gas

(iii) the change in volume of the gas when it was heated at constant pressure