4) For each of the following reactions, calculate 4G from their reaction enthalpy and reaction entropy values. (a) 2 CHCHO(g) +0,(g)+2 CHCOOH(1) (b) 2 AgCl(s) + Br_(1) 2 AgBr(s) + Cl2(g) (c) Hg(1) + Cl2(g) HgCl,(s) 5) For the reactions in no. 4, calculate AG from their AG values