dG = dH - TdS
dG = -93 - 356(-0.198) = ?
If - it's spontaneous?
If ammonia is manufactured at 356 K, is the reaction spontaneous, given that the enthalpy and entropy change for the reaction are -93 kJ/mol and -198 J/mol K, respectively?
A. Yes, the ΔG is -92 kJ/mol.
B. No, the ΔG is 92 kJ/mol.
C. No, the ΔG is 22.5 kJ/mol.
D. Yes, the ΔG is -22.5 kJ/mol.
3 answers
yes, it is spontaneous at -22.5 kJ/mol
you have to work backwards
try all of the answers:
dG = -22.5 = -93 - (-198 x T)
= -22.5 + 93 = - (-198 x T)
= 70.5 = 198 x T
= 0.356 = T
we see that C is the only answer that works
try all of the answers:
dG = -22.5 = -93 - (-198 x T)
= -22.5 + 93 = - (-198 x T)
= 70.5 = 198 x T
= 0.356 = T
we see that C is the only answer that works