Calculate `DeltaS_(f)^(@)` at 298 K of , (i) NaCl(s), (ii) `NH_(4)Cl(s)` & diamond The values of `S^(@)` of Na, `Cl_(2), NaCl, NH_(4)Cl,N_(2),H_(2)`, diamond & graphite are 51, 223, 72, 95, 192, 131, 2.43 & 5.69 `JK^(-1)mol^(-1)` respectively.

Calculate lambda_(m)^(@) for NH_(4)OH given that values of lambda_(m)^(@) for Ba(OH)_(2), BaCl_(2) and NH_(4)Cl as 523.28, 280.0 and 129.8 S cm^(2) mol^(-1) respectively

Calculate lamda_(m)^(@) for NH_(4)OH given that values of lamda_(m)^(@) for Ba(OH)_(2), BaCl_(2) and NH_(4)Cl as 523.28, 280.0 and 129.8 S cm^(2) mol^(-1) respectively.

Calculate Delta G (in kJ) for the reaction at 300 K, H_(2)(g)+Cl_(2)(g) rarr 2HCl (g) Given at 300 K, BE_(H-H) = 435 kJ mol^(-1), BE_(Cl-Cl) = 240 kJ mol^(-1), BE_(HCl) = 430 kJ mol^(-1) Entropies of H_(2), Cl_(2) and HCl are 131, 223 and 187 JK^(-1) mol^(-1) respectively.

The standard entroples of N_(2)(g), H_(2) (g) and NH_(3) (g) are 191.5, 130.5, 192.6 Jk^(-1) mol ^(-1) . The value of DeltaS^(@) of formation of ammonia is

Calculate free energy change for the reaction, H_(2)(g)+Cl_(2)(g)to2H-Cl(g) By using the bond energy and entropy data. Bond energies of H-H,Cl-Cl and H-Cl bonds are 435kJ mol^(-1),240jK" "mol^(-1) and 430jk" "mol^(-1) respectively standard entropies of H_(2),Cl_(2) and HCl are 130.59,222.95 and 186.68 JK^(-1)" "mol^(-1) respectively.

Consider the synthesis of ammonia: {:(N_(2) (g) + 3 H_(2) (g) rarr 2NH_(3) (g),,,Delta_(r )H^(@)=-92.6 kJ):} If absolute entropies of N_(2) (g), H_(2) (g) , and NH_(3) (g) are 192 j K^(-1) mol^(-1), 131 jK^(-1) mol^(-1) , and 193 j k^(-1) , respectively, at 25^(@)C , predict whether the reaction is spontaneous or not. Strategy : Calculate Delta S_("univ") using Delta S_("says") and Delta S_("surr") . For calculating Delta S_("rays") use the absolute entropies of reactants and product. For calculating Delta S_("surr") , use Delta_(r) H^(@) and T .