Which has more entropy ? 1 mol `H_(2)O (I) " at " 25^(@)C or 1 mol H_(2)O(I) " at " 35^(@)C`.

What is entropy change?Predict the sign of entropy chsnge in each of the following giving reasons for your predictions : (i) H_(2) (at 25^(@)C, 1 atm) to H_(2)(at 25^(@)C and 10 atm)) (ii) H_(2)O(at 25^(@)C, 1 atm ) to H_(2)O(at 50^(@)C and 1 atm)) (iii) 2NH_(4)NO_(3)(s) to 2N_(2)(g) + 4H_(2)O(g) + O_(2)(g)

Calculate the change in enthalpy for the following process at 1 atm H_(2)O(1, 50^(@)C) rarr H_(2)O (g, 150^(@)C) given that Delta H_(v) at 100^(@)C is 40.7 kJ mol^(-1) C_(p)(H_(2)O, l) = 75.0 J mol^(-1)K^(-1) C_(p)(H_(2)O, g) = 33.3 J mol^(-1)K^(-1)

Find the entropy change when 90 g of H_(2)O at 10^(@) C was converted into steam at 100^(@) C. [Given C_(P)(H_(2)O)=75.29 JK^(-1)mol^(-1) and Delta H_("vap")=43.932 JK^(-1)mol^(-1) ]

For the reaction 2H_(2)(g)+ O_(2)(g)to 2H_(2)O(l) . The standard entropies of H_(2)(g),O_(2)(g)" and "H_(2)O(l) " at "27^(@)C " are " 30 "cal K"^(-1)mol^(-1),50cal K^(-1) and15cal K^(-1)mol^(-1) "respectivley" . Assuming H_(2) " and " O_(2) to behave as ideal gas (without vibrational degree of freedom ) and C_((PmH_(2)O(l)))=15.5 calK^(-1)mol^(-1) . Determine magnitude of standard entropy (in calK^(-1) ) change for the reaction at 177^(@)C . ltbrlt [Given : R =2 calK^(-1)mol^(-1),"In " 1.5 =0.4 ]

The standard molar entropy of H_(2)O(l) is 70 JK^(-1)mol^-1 . Standard molar entropy of H_(2)O(s) is

Calculate the entropy change accompanying the following change of state 5 mol of O_(2) (27^(@)C, 1 atm) rarr 5 mol of O_(2) (117^(@)C, 5 atm) C_(P) for O_(2) = 5.95 cal deg^(-1) mol^(-1)

Heat of formation of H_(2)O(g) at 1 atm and 25^(@)C is -243KJ . DeltaE for the reaction H_(2)(g)+30JK^(-1)mol^(-1)(1)/(2) O(g)rarrH_(2)O(g) at 25^(@)C is

The following are the heats of reactions - (i) Delta H_(f)^(@) of H_(2)O_((l))=-68.3 "K cal mol"^(-1) (ii) Delta H_("comb.")^(@) of C_(2)H_(2)=-337.2 "K cal mol"^(-1) (iii) Delta H_("comb.")^(@) of C_(2)H_(4)=-363.7 "K cal mol"^(-1) Then heat change for the reaction C_(2)H_(2)+H_(2)rarr C_(2)H_(4) is -