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 -22.5 kJ/mol.
B. No, the ΔG is 92 kJ/mol.
C. Yes, the ΔG is -92 kJ/mol.
D. No, the ΔG is 22.5 kJ/mol.

Question

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 -22.5 kJ/mol.
 		B.	No, the ΔG is 92 kJ/mol.
 		C.	Yes, the ΔG is -92 kJ/mol.
 		D.	No, the ΔG is 22.5 kJ/mol.

vera_ewing · Answer

@aaronq Please help me!

aaronq · Answer

use the formula $\Delta G=\Delta H-T\Delta S$

vera_ewing · Answer

@aaronq So I got 22.5 so it's D?

aaronq · Answer

post what you did?

vera_ewing · Answer

@aaronq 356-(198)(93) is this the right formula?

aaronq · Answer

H is enthalpy, S is entropy, T is temp

vera_ewing · Answer

-93-356 K(-198) Ok I got 70395?! @aaronq

vera_ewing · Answer

@aaronq I didn't get one of the answer choices...

aaronq · Answer

watch the units of H

vera_ewing · Answer

@aaronq I was wrong...why did I get 70395? And not one of the answer choices?

aaronq · Answer

look at the units of H, they're in kJ/mol you need to convert them to J/mol