How do you figure this question out? And no, the answer isn't 13.9, dividing by 2 doesn't work?

Question

The equilibrium constant Kc for the equation


CS2(g) + 4H2(g) = CH4(g) + 2H2S(g)


at 900oC is 27.8. What is the value of Kc for the following equation?


1/2CS2(g) + 2H2(g) = 1/2CH4(g) + H2S(g)

Answer 1

It's been a while since I've done any chemistry, but I believe the equilibrium constant Kc for the equilibrium

CS2(g) + 4H2(g) <=> CH4(g) + 2H2S(g)

is given by

Kc = [CH4] [H2S]^2 / [CS2] [H2]^4

in which case, taking the square root of both sides, we have

[CH4]^(1/2) [H2S] / [CS2]^(1/2) [H2]^2 = Kc^(1/2)

If you look at the left-hand side, it's equal to the equilibrium constant for the equilibrium

1/2CS2(g) + 2H2(g) <=> 1/2CH4(g) + H2S(g)

So then the equilibrium constant would just be the square root of 27.8, or 5.27.

Answer 2

Try asking in the chemistry section.

Answer 3

how would i know.
dont ask me.
ask some ned or something