# Problem: A 1.00 liter flask contained 0.24 mol NO2 at 700 K which decomposed according to the reaction 2 NO2(g) ⇌ 2NO(g) + O2(g). Determine Kc given that when equilibrium was achieved, 0.14 mol NO was present.a. 4.7x10-2b. 6.9x10-3c. 2.4x10-2d. 1.4x10-1e. 9.8x10-2

###### FREE Expert Solution

We are being asked to calculate the equilibrium constant, Kc for the given equilibrium reaction:

2 NO2(g) 2 NO(g) + O2(g)

When dealing with equilibrium and Kc:

Kc → equilibrium units are in molarity
Kc is an equilibrium expression:

$\overline{){{\mathbf{K}}}_{{\mathbf{c}}}{\mathbf{=}}\frac{\mathbf{products}}{\mathbf{reactants}}}$

only aqueous and gaseous species are included in the equilibrium expression
▪ the coefficient of each compound in the reaction equation will be the exponent of the concentrations in the equilibrium expression

Recall molarity:

Given:

97% (114 ratings) ###### Problem Details

A 1.00 liter flask contained 0.24 mol NO2 at 700 K which decomposed according to the reaction 2 NO2(g) ⇌ 2NO(g) + O2(g). Determine Kc given that when equilibrium was achieved, 0.14 mol NO was present.

a. 4.7x10-2
b. 6.9x10-3
c. 2.4x10-2
d. 1.4x10-1
e. 9.8x10-2