When the following reactions come to equilibrium, does the equilibrium mixture contain mostly reactants or mostly products? (a) N2(g) + O2(g) ⇌ 2 NO(g), Kc = 1.5 × 10^-10 (b) 2 SO2(g) + O2(g) ⇌ 2 SO3(g), Kp = 2.5 × 10^9

Name: Chemistry: The Central Science
Author: Brown
ISBN: 9780134414232

검증된 단계별 안내

Step 1: Understand the concept of equilibrium constant (K). The equilibrium constant (K) is a measure of the extent of a reaction at equilibrium. A large K value (K >> 1) indicates that the reaction favors the formation of products, while a small K value (K << 1) indicates that the reaction favors the formation of reactants.

Step 2: Analyze reaction (a) N2(g) + O2(g) ⇌ 2 NO(g) with Kc = 1.5 × 10^-10. Since Kc is much less than 1, this suggests that at equilibrium, the concentration of reactants (N2 and O2) is much greater than the concentration of products (NO).

Step 3: Conclude for reaction (a) that the equilibrium mixture contains mostly reactants because the equilibrium constant is very small, indicating the reaction does not proceed far towards products.

Step 4: Analyze reaction (b) 2 SO2(g) + O2(g) ⇌ 2 SO3(g) with Kp = 2.5 × 10^9. Since Kp is much greater than 1, this suggests that at equilibrium, the concentration of products (SO3) is much greater than the concentration of reactants (SO2 and O2).

Step 5: Conclude for reaction (b) that the equilibrium mixture contains mostly products because the equilibrium constant is very large, indicating the reaction proceeds significantly towards products.

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Chemical Equilibrium

Chemical equilibrium occurs when the rates of the forward and reverse reactions are equal, resulting in constant concentrations of reactants and products. At this point, the system is dynamic, meaning that reactions continue to occur, but there is no net change in the concentrations of the substances involved.

Equilibrium Constant (K)

The equilibrium constant (K) quantifies the ratio of the concentrations of products to reactants at equilibrium for a given reaction at a specific temperature. A large K value (much greater than 1) indicates that products are favored at equilibrium, while a small K value (much less than 1) suggests that reactants are favored.

Le Chatelier's Principle

Le Chatelier's Principle states that if a system at equilibrium is disturbed by changes in concentration, temperature, or pressure, the system will adjust to counteract the disturbance and restore a new equilibrium. This principle helps predict how changes will affect the position of equilibrium in a reaction.