Question

The equilibrium constant K for the reaction:
$2HI\left(g\right)\rightleftharpoons H_2\left(g\right)+I_1\left(g\right)$ at room temp is 2.85 and that at 698 K is $1.4\times {10}^{-2}$. This implies that the forward reaction is:

• A. exothermic
• B. endothermic
• C. exergonic
• D. unpredictable

Answer 1

The correct option is A exothermic

With the increase of temperature, k value decreases, so that forward reaction decreases with increase of temperature. This implies that reaction will proceed in forward direction with decrease of temperature, i.e., heat is liberated and hence forward reaction is exothermic.