A3. A4. A5. 1 kg of air (molecular weight of 28.97 kg/kmol, assumed to be ideal gas) and its specific heat capacity (cp) at a constant pressure is 0.97 kJ/kgK. Given that the universal gas constant is 8314 J/kmole K. (a) Determine the specific heat ratio, y. [Given: R= Cp - Cv; Y = (Cp/ Cv)] (b) Calculate the change in specific internal energy when the gas is heated at constant volume from 50 C to 150 C. A brick wall of 2.5 m width and 4 m height has different surface temperatures on both sides at 10 C and 30 C, respectively. If the wall thickness is 14 cm and the thermal conductivity of brick wall is 0.13 W/mK. Calculate : (a) the heat conduction rate (in W); and (b) the amount of heat energy conducted (in kJ) in one hour. A closed rigid chamber containing water was cooled from 220 C to 100 C. Given the specific volume of water is 0.03 m/kg. (a) Determine the phase before cooling. (b) Determine the specific volume and dryness fraction after cooling. (c) Sketch a temperature-specific volume (T-v) diagram for the and indicate the states before and after cooling clearly. process (6 marks) (2 marks) (5 marks) (3 marks) (2 marks) (3 marks) (3 marks)