(a) what two conditions have to be satisfied for a sample of a real gas for its be- haviour to be considered ideal? [1 mark] (b) explain why the constant volume molar heat capacity cy of an ideal diatomic bas is larger than that of an ideal monatomic gas, (5/2)r compared to (3/2)r at moderate temperatures. [2 marks nitrogen is a diatomic gas of molar mass m = 28.0 g mol-1 . the ratio of its molar heat capacities at constant pressure and volume is y = cp/cv = 7/5. (you may treat the nitrogen sample described in this question as an ideal gas.) seven grams of nitrogen initially at pressure of 300kpa and temperature of 27 °c are cooled at constant volume until the pressure is 100 kpa. (c) what is the original volume of the gas? [2 marks] [1 mark] (d) what is the temperature of the gas after the compression? the gas sample is then compressed adiabatically until it reaches its original pressure of 300 kpa [2 marks (e) what is the new volume of the gas? [1 mark (f) what is the new temperature of the gas? (g) how much work is done on the gas during the adiabatic compression of the ni- trogen? [1 mark] finally, the gas is heated isobarically until it returns to its initial volume, completing cyclic process a (h) sketch the full three-step cycle on a pv diagram. show the 100 k and 300 k isotherms and identify a feature of the graph corresponding to the total work done in the cycle