Consider the reaction: N₂(g) + 3 H₂(g) ⇌ 2 NH₃(g) Complete the table. Assume that all concentrations are equilibrium concentrations in M.
T (K) [N₂] [H₂] [NH₃] K_c
500 0.115 0.105 0.439 _
575 0.110 _ 0.128 9.6
775 0.120 0.140 _ 0.0584

Verified step by step guidance

1. Identify the balanced chemical equation for the reaction: \( N_2(g) + 3H_2(g) \rightleftharpoons 2NH_3(g) \).
2. Use the equilibrium constant expression for the reaction: \( K_c = \frac{[NH_3]^2}{[N_2][H_2]^3} \).
3. For the first row (T = 500 K), plug the given concentrations into the equilibrium expression to verify the provided \( K_c \) value.
4. For the second row (T = 575 K), use the given \([N_2]\), \([NH_3]\), and the calculated \( K_c \) from the first row to solve for the missing \([H_2]\) concentration.
5. For the third row (T = 775 K), use the given \([N_2]\), \([H_2]\), and the calculated \( K_c \) from the first row to solve for the missing \([NH_3]\) concentration.

Key Concepts

Chemical Equilibrium

Chemical equilibrium occurs when the rates of the forward and reverse reactions are equal, resulting in constant concentrations of reactants and products. In this state, the system is dynamic, meaning that reactions continue to occur, but there is no net change in concentration. Understanding this concept is crucial for analyzing equilibrium constants and predicting how changes in conditions affect the system.

Equilibrium Constant (Kc)

The equilibrium constant (Kc) is a numerical value that expresses the ratio of the concentrations of products to reactants at equilibrium, each raised to the power of their coefficients in the balanced equation. It provides insight into the position of equilibrium; a larger Kc indicates a greater concentration of products, while a smaller Kc suggests more reactants. Calculating Kc is essential for completing the provided table.

Concentration Units (Molarity)

Molarity (M) is a unit of concentration defined as the number of moles of solute per liter of solution. It is commonly used in chemical equations and equilibrium expressions to quantify the amounts of reactants and products. Understanding how to convert between moles and molarity is vital for accurately filling in the missing values in the equilibrium concentration table.