Given the standard enthalpy changes for the following two reactions: (1) Zn(s) + Cl2(g) ZnCl2(s) AH = -415.0 kJ (2) Pb(s) + Cl2(g) PbCl2(S) AH = -359.4 kJ what is the standard enthalpy change for the reaction: (3) Zn(s) + PbCl2(3)ZnCl2(8) + Pb(s) AH = ? kJ Given the standard enthalpy changes for the following two reactions: (1) N2(g) + 202(g) N204(g) AH = 9.2 kJ (2) 2N2O(g) +2N2(g) + O2(g) AH= -164.2 kJ what is the standard enthalpy change for the reaction: (3) 2N2O(g) + 302(g) +2N204(8) -2N204(g) AH = ? kJ