Consider the reaction represented by the equation: N2O4(g) ⇌ 2NO2(g) ; ∆H = + x kJmol-1. What happens when the temperature is reduced at equilibrium?

A. Concentration of N2O4(g) decreases
B. Concentration of N2O4(g) increases.
C. Pressure exerted by the gases increases
D. Pressure exerted by the gases remains constant

Correct Answer: Option B

B. Concentration of N2O4(g) increases.