Use Le Châtelier’s principle to explain the following changes in the solubility of Ag2CO3 in water. (a) Decrease on addition of AgNO3 (b) Increase on addition of HNO3 (c) Decrease on addition of Na2CO3 (d) Increase on addition of NH3

Name: Chemistry
Author: McMurry
ISBN: 9781292336145

검증된 단계별 안내

Step 1: Identify the equilibrium reaction for the dissolution of Ag2CO3 in water: Ag2CO3(s) \(\rightleftharpoons\) 2Ag^+(aq) + CO3^{2-}(aq).

Step 2: (a) Addition of AgNO3 increases the concentration of Ag^+ ions. According to Le Châtelier’s principle, the equilibrium will shift to the left to reduce the stress of increased Ag^+ concentration, decreasing the solubility of Ag2CO3.

Step 3: (b) Addition of HNO3 introduces H^+ ions, which react with CO3^{2-} ions to form H2CO3, reducing CO3^{2-} concentration. The equilibrium shifts to the right to replace the CO3^{2-} ions, increasing the solubility of Ag2CO3.

Step 4: (c) Addition of Na2CO3 increases the concentration of CO3^{2-} ions. The equilibrium shifts to the left to reduce the stress of increased CO3^{2-} concentration, decreasing the solubility of Ag2CO3.

Step 5: (d) Addition of NH3 forms a complex with Ag^+ ions (Ag(NH3)2^+), reducing the free Ag^+ ion concentration. The equilibrium shifts to the right to replace the Ag^+ ions, increasing the solubility of Ag2CO3.

주요 개념

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

Le Châtelier’s Principle

Le Châtelier’s principle states that if a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium shifts to counteract the change. This principle is crucial for predicting how the solubility of a compound, like Ag2CO3, will respond to various external changes, such as concentration or pressure.

Solubility Product Constant (Ksp)

The solubility product constant (Ksp) is an equilibrium constant that applies to the solubility of sparingly soluble ionic compounds. For Ag2CO3, the Ksp value helps determine how changes in concentration of ions in solution affect its solubility, guiding predictions about the effects of adding different substances.

Common Ion Effect

The common ion effect refers to the decrease in solubility of an ionic compound when a common ion is added to the solution. In the case of Ag2CO3, adding AgNO3 introduces Ag+ ions, which shifts the equilibrium to the left, reducing the solubility of Ag2CO3 due to the increased concentration of the common ion.