Chapter 17, Problem 1ALQ

Consider an equilibrium mixture of four chemicals (A. B. C. and D. all gases) reacting in a closed flask according to the following equation:
$\text{A}+\text{B}\rightleftharpoons \text{C}+\text{D}$   a. You add more A to the flask. How does the concentration of each chemical compare to its original concentration after equilibrium is re-established? Justify your answer.
h. You have the original set-up at equilibrium, and add more D to the flask. How does the concentration of each chemical compare to its original concentration after equilibrium is re-established? Justify your answer.

Interpretation Introduction

(a)

Interpretation:

The concentration of each chemical in the given equilibrium mixture when more A is added is to be compared with original concentration after equilibrium is reestablished.

Concept Introduction:

Le-Chatelier principle states that the when a dynamic equilibrium is subjected to a change, the equilibrium moves in a direction so as to counteract that change. If the concentration of one of the compounds in the equilibrium is increased or decreased, the equilibrium will move in a direction to decrease/increase the concentration of that compound.

Answer to Problem 1ALQ

The concentration of A will decrease and the concentration of C and D increases.

Explanation of Solution

The given equilibrium is,

$\text{A+B}\rightleftharpoons \text{C+D}$

To the given equilibrium when more amount of A is added, the equilibrium will shift towards the forward direction in order to decrease the concentration of A. Since the equilibrium has constant value so, when the reaction moves towards the forward direction the concentration of C and D increases as compared to the original concentration.

Interpretation Introduction

(b)

Interpretation:

The concentration of each chemical in the given equilibrium mixture when more D is added is to be compared with original concentration after equilibrium is reestablished.

Concept Introduction:

Le-Chatelier principle states that the when a dynamic equilibrium is subjected to a change, the equilibrium moves in a direction so as to counteract that change. If the concentration of one of the compounds in the equilibrium is increased or decreased, the equilibrium will move in a direction to decrease/increase the concentration of that compound.

Answer to Problem 1ALQ

The concentration of D decrease and the concentration of A and B increases.

Explanation of Solution

The given equilibrium is,

$\text{A+B}\rightleftharpoons \text{C+D}$

To the given equilibrium when more amount of D is added, the equilibrium will shift towards the backward direction in order to decrease the concentration of D. Since the equilibrium has constant value so, when the reaction moves towards the backward direction the concentration of A and B increases as compared to the original concentration.