Each reaction is allowed to come to equilibrium, and then the volume is changed as indicated. Predict the effect (shift right, shift left, or no effect) of the indicated volume change. b. PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) (volume is increased)

Verified step by step guidance

1. Identify the reaction: \( \text{PCl}_3(\text{g}) + \text{Cl}_2(\text{g}) \rightleftharpoons \text{PCl}_5(\text{g}) \).
2. Recognize that this is a gaseous equilibrium reaction, and volume changes affect the equilibrium position according to Le Chatelier's Principle.
3. Determine the number of moles of gas on each side of the equilibrium: the left side has 2 moles (1 mole of \( \text{PCl}_3 \) and 1 mole of \( \text{Cl}_2 \)), and the right side has 1 mole (\( \text{PCl}_5 \)).
4. Understand that increasing the volume of the container decreases the pressure, and the system will shift to the side with more moles of gas to counteract this change.
5. Conclude that the equilibrium will shift to the left, towards the side with more moles of gas (\( \text{PCl}_3 \) and \( \text{Cl}_2 \)).

Key Concepts

Le Chatelier's Principle

Le Chatelier'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 helps predict how a system at equilibrium responds to changes in concentration, temperature, or pressure.

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. Changes in volume affect the concentrations of gaseous reactants and products, which can influence the position of equilibrium and the value of K.

Effect of Volume Change on Gaseous Reactions

In gaseous reactions, increasing the volume decreases the pressure, which can shift the equilibrium position. According to Le Chatelier's Principle, if the reaction produces fewer moles of gas on the product side, the equilibrium will shift to the right (toward products) to increase pressure, and vice versa for a decrease in volume.