posted by Chem .
N2 + 3H2 --> 2NH3
At 25°C (delta)Ho = -92.22 kJ and (delta)So = -198.53 J/K. Using this information, calculate the equilibrium constant for the reaction at 2.43x10^2°C. (R = 8.314 J/K)
Apparently the way I'm doing it is wrong:
I divide 198.53 by 1000 then multiply by 298 to get delta(S). Then I subtract this from delta(H) to get delta(G). Then I multiply 516 with .008314... I take this answer and divide delta(G) by it, then multiply by -1. I take this to the e power... Then I use the equation Kc = (RT)^-n * Kp to get the equilibrium constant. However my answer is still wrong.
or mike or whomever,
1. How do you know to calculate Kc instead of Kp? The problem doesn't specify which. Since this is a gaseous reaction, Kp may be what they are looking for.
2. Have you tried the van't Hoff equation. You have delta H and one T so the van't Hoff equation can be used to calculate K at any other T.