Consider the following equilibrium reaction having gaseous reactants and products. 4HCl + O2 ⇌ 2H2O + Cl2 Which of the following would result from increasing the concentration of H2O?

The reaction will proceed backward, thus shifting the equilibrium position to the left.

Explanation:

4HCl + O2 ⇌ 2H2O + Cl2

Increasing the concentration of H2O will cause the reaction to proceed backward, thus shifting the equilibrium position to the left. This is so because increasing the concentration of the product of a system in equilibrium will cause the products to react to form back the reactant thereby causing the reaction to proceed backward as explained by Le Chatelier's principle.

the rate of reaction will increase

Explanation:

Le chatelier principle states that chnging a factor such as concentration, temperature, or pressure of a reaction at equilibrium will cause the reaction to shift in the direction that counteracts the effect of that change.

Therefore, when reactants are added to a reaction at equilibrium shift when more reactants are added then the reaction shifts to the right to make more products.