Using this data,

Question

2 NO(g) + Cl2(g) == 2 NOCl(g) Kc = 3.20 X 10-3
NO2(g) == NO(g) + ½ O2(g) Kc = 3.93
calculate a value for Kc for the reaction,

NOCl (g) + ½ O2 (g) == NO2 (g) + ½ Cl2 (g)

A. 20.2
B. 2.06 X 10-4
C. 4.49
D. 4.84 X 10-3
E. 0.223

eliminated down to b or d
but going with b unless wrong

Answer 1

I disagree with b AND d.
Use equation 1, take 1/2 of it, and reverse it. K1 for that will be 1/sqrt Kc.
Multiply k1 by equation 2 reversed so k2 = 1/Kc
Then k1*k2 = ?
Check my manipulations to be sure you get the equation in the problem.

Answer 2

when you reverse it do you get a negative?

Answer 3

no negatives