Chapter 15.6, Problem 3RC

Interpretation Introduction

Interpretation:

By analyzing different values of equilibrium constant $K$ at different temperature, it should be determined that the given reaction is exothermic or endothermic.

Concept introduction:

• Chemical equilibrium is the state at which there is no further change in concentration of reactants and products. The rate of forward and backward reaction is equal at equilibrium.
• Equilibrium constant: at equilibrium the ratio of products to reactants (each raised to the power corresponding to its stoichiometric coefficient) has a constant value, K

For a general reaction, $\text{aA+bB}\rightleftarrows \text{cC+dD}$

$\text{Equilibrium}\text{constant}\text{K}\text{=}\frac{{\left[\text{C}\right]}^{\text{c}}{\left[\text{D}\right]}^{\text{d}}}{{\left[\text{A}\right]}^{\text{a}}{\left[\text{B}\right]}^{\text{b}}}$

• Increasing the temperature decreases the value of equilibrium constant.
• Exothermic reaction release energy to their surrounding and thus temperature is increases and an endothermic reaction absorbs energy from their surroundings.