Q.10.85 - An Introduction to General, Organic, and Biological Chemistry

Question

Use Le Châtelier's principle to predict if each of the following changes causes the system to shift in the direction of products or reactants: 

${\mathrm{H}}_2\mathrm{S}\left(aq\right)+{\mathrm{H}}_2\mathrm{O}\left(l\right)\rightleftarrows {\mathrm{H}}_3{\mathrm{O}}^{+}\left(aq\right)+{\mathrm{HS}}^{-}\left(aq\right)$

a. adding more ${\mathrm{H}}_2\mathrm{S}\left(aq\right)$

b. removing some ${\mathrm{HS}}^{-}\left(aq\right)$

c. adding more ${\mathrm{H}}_3{\mathrm{O}}^{+}\left(aq\right)$

d. removing some ${\mathrm{H}}_2\mathrm{S}\left(aq\right)$

Step-by-Step Solution

Answer

Part a. Equilibrium shift towards products

Part b. Equilibrium shift towards products 

Part c. Equilibrium shift towards reactants

Part d. Equilibrium shift towards reactants 

Step 1: Given Information (Part a)

Le Châtelier's principle indicates that a pressure brought about by adding a substance at equilibrium is relieved when the framework shifts the reaction away from that substance. At the point when a portion of a substance is taken out, the equilibrium framework shifts in the direction of that substance.

Step 2: Explanation Part (a)

Whenever weight on the equilibrium increases by increasing the concentration of one of the reactants, $H_{2}S$ , the framework relieves pressure by increasing the pace of the forwarding reaction. Along these lines, the framework shifts towards items until equilibrium is restored.

Step 3: Explanation Part (b)

At the point when some measure of $H{S}^{-}$, one of the items is taken out, the pace of reverse reaction diminishes. Subsequently, the framework shifts towards the forwarding direction to deliver a greater amount of the items until equilibrium is reestablished.

Step 4: Explanation Part (c)

Whenever weight on the equilibrium increases by increasing the concentration of one of the items, $H_3{O}^{+}$, the framework relieves pressure by increasing the pace of reverse reaction. In this way, the framework shifts towards reactants until equilibrium is restored.

Step 5: Explanation Part (d)

When $H_{2}S$, one of the reactants is eliminated, the pace of forwarding reaction diminishes. Thus, the framework shifts towards the reactants until equilibrium is restored.