Skip to main content
Pearson+ LogoPearson+ Logo
Ch.15 - Chemical Equilibrium
All textbooksBrown 14th EditionCh.15 - Chemical EquilibriumProblem 41a
Chapter 15, Problem 41a

(a) If Qc < Kc, in which direction will a reaction proceed in order to reach equilibrium?

Verified step by step guidance
1
Identify the given terms: Q_c is the reaction quotient, and K_c is the equilibrium constant.
Understand the relationship: If Q_c < K_c, it means the concentration of products is less than what is required at equilibrium.
Determine the direction: The reaction will proceed in the forward direction to produce more products and reach equilibrium.
Visualize the process: As the reaction moves forward, the concentration of reactants will decrease, and the concentration of products will increase.
Conclude the reasoning: The reaction continues in the forward direction until Q_c equals K_c, achieving equilibrium.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
1m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Reaction Quotient (Q<sub>c</sub>)

The reaction quotient, Q<sub>c</sub>, is a measure of the relative concentrations of products and reactants at any point in a reaction. It is calculated using the same expression as the equilibrium constant (K<sub>c</sub>), but with the current concentrations instead of equilibrium concentrations. Q<sub>c</sub> helps determine the direction in which a reaction will shift to reach equilibrium.
Recommended video:
Guided course
00:49
Reaction Quotient Q

Equilibrium Constant (K<sub>c</sub>)

The equilibrium constant, K<sub>c</sub>, is a value that expresses the ratio of the concentrations of products to reactants at equilibrium for a given reaction at a specific temperature. It is a fixed value for a particular reaction under specified conditions. Comparing Q<sub>c</sub> to K<sub>c</sub> allows us to predict the direction of the reaction's shift towards equilibrium.
Recommended video:
Guided course
01:14
Equilibrium Constant K

Le Chatelier's Principle

Le Chatelier's Principle states that if a system at equilibrium is disturbed by a change in concentration, temperature, or pressure, the system will adjust to counteract the disturbance and restore a new equilibrium. In the context of Q<sub>c</sub> and K<sub>c</sub>, if Q<sub>c</sub> is less than K<sub>c</sub>, the reaction will shift to the right, favoring the formation of products to achieve equilibrium.
Recommended video:
Guided course
07:32
Le Chatelier's Principle
Related Practice
Textbook Question

A mixture of 0.2000 mol of CO2, 0.1000 mol of H2, and 0.1600 mol of H2O is placed in a 2.000-L vessel. The following equilibrium is established at 500 K: CO2(g) + H2(g) ⇌ CO(g) + H2O(g) (d) Calculate Kc for the reaction.

1
views
Textbook Question

(b) What condition must be satisfied so that Qc = Kc?

1
views
Textbook Question

(a) If Qc > Kc, how must the reaction proceed to reach equilibrium?

Textbook Question

(b) At the start of a certain reaction, only reactants are present; no products have been formed. What is the value of Qc at this point in the reaction?