In: Chemistry
A steel reaction vessel at 25 oC initially contained pure NO2 at a concentration of 2.0 x 10-4 mol/L. Some of the NO2 reacted to form N2O4 as described by the following equilibrum equation:
2NO2(g) <----------> N2O4(g)
At equilibrium, the concentration of N2O4 was found to be 6.01 x 10-6 mol/L. What is the concentration-based equilibrium constant (Kc) for this reaction at 25 oC?
I know the correct answer is 170, but I'd like to know how to get there. Thanks!
2NO2(g)
N2O4(g)
initial conc(mol/L) 2.0x10-4 0
change -2a +a
Equb conc 2.0x10-4 - 2a a
Given Equilibrium concentration of N2O4 = a = 6.01 x 10-6 mol/L
So Equilibrium concentration of NO2 is = 2.0x10-4 - 2a
= 2.0x10-4 - (2x6.01 x 10-6)
= 1.88x10 -4 mol/L
Equilibrium constant ,