Calculate Kc for each reaction. a. N2(g) + 3 H2(g) ⇌ 2 NH3(g) Kp = 6.2×10^5 (at 298 K)

Verified step by step guidance

1. Identify the relationship between Kc and Kp using the equation: Kp = Kc(RT)^Δn, where Δn is the change in moles of gas.
2. Calculate Δn for the reaction: Δn = moles of gaseous products - moles of gaseous reactants. For the given reaction, Δn = 2 - (1 + 3).
3. Substitute the values into the equation: Kp = Kc(RT)^Δn. Use R = 0.0821 L·atm/mol·K and T = 298 K.
4. Rearrange the equation to solve for Kc: Kc = Kp / (RT)^Δn.
5. Substitute the known values (Kp, R, T, and Δn) into the equation to find Kc.

Key Concepts

Equilibrium Constant (Kc and Kp)

The equilibrium constant (K) quantifies the ratio of the concentrations of products to reactants at equilibrium for a given reaction. Kc refers to concentrations in molarity, while Kp refers to partial pressures. The relationship between Kc and Kp is given by the equation Kp = Kc(RT)^(Δn), where Δn is the change in moles of gas. Understanding this relationship is crucial for converting between Kc and Kp.

Reaction Stoichiometry

Stoichiometry involves the quantitative relationships between reactants and products in a chemical reaction. In the given reaction, the stoichiometric coefficients indicate the molar ratios of nitrogen, hydrogen, and ammonia. This is essential for calculating the equilibrium constant, as it determines how the concentrations of each species relate to one another at equilibrium.

Temperature Dependence of Equilibrium Constants

Equilibrium constants are temperature-dependent, meaning that Kc and Kp values can change with temperature variations. The provided Kp value is specific to 298 K, and any calculations involving Kc must consider this temperature. Understanding how temperature affects the position of equilibrium is vital for accurately calculating and interpreting Kc in relation to Kp.