Equilibrium Molarity Calculation: How to Determine the Equilibrium Concentration of a Component in a Chemical Reaction

How can we calculate the equilibrium molarity of a component in a chemical reaction?

Given the equilibrium constant for a reaction and initial concentrations of reactants, how do we determine the equilibrium concentration of a product?

Explanation:

Calculating the equilibrium molarity of a component in a chemical reaction involves using the equilibrium constant and the concentrations of reactants and products at equilibrium. Let's dive into an example to understand the process.

When dealing with chemical reactions, the equilibrium constant plays a crucial role in determining the equilibrium concentrations of the reactants and products. In this case, the equilibrium constant for the reaction is 6.28 at a specific temperature.

For the reaction of nitrogen (N2) and hydrogen (H2) to form ammonia (NH3), the equilibrium constant (Keq) is 6.28. Suppose the initial concentration of nitrogen ([N2]) is 1.88 M and the equilibrium concentration of ammonia ([NH3]) is 6.62 M.

To calculate the equilibrium concentration of hydrogen ([H2]), we can use the equilibrium constant expression and the given concentrations. The equilibrium constant expression for the reaction N2 + 3H2 = 2NH3 is ([NH3]² / ([N2] * [H2]³)). By substituting the values of [NH3] and [N2], we can solve for [H2].

After rearranging the equation and evaluating the numerical expression, we find that the equilibrium concentration of hydrogen ([H2]) is 1.19 M. This value represents the equilibrium molarity of hydrogen in the reaction.

It is essential to verify the calculated equilibrium molarity using your own calculations to ensure accuracy. Understanding how to calculate equilibrium concentrations is crucial in chemical equilibrium studies.