14. Propyne reacts with hydrogen as follows: CHelg) + 2H2(g) CH3(g) AH' =-287 kJ a) Calculate the standard entropy change of this reaction, given the following additional information: CH (B) AS = 248 JK'mol, Hz(8) AS* = 131 JK mol?, CHe(g) AS = 270 JK mot? [3 marks) b) Calculate the standard free energy change at 298K for the reaction in part (a). [3 marks]