Consider the following mechanism for the decomposition of nitramide 1NH2NO22 in aqueous solution: NH2NO21aq2 + OH-1aq2S NHNO2 -1aq2 + H2O1l2 NHNO2 -1aq2S N2O1g2 + OH-1aq2 (c) How will the rate of the overall reaction be affected if HCl is added to the solution?

Verified step by step guidance

1. Identify the role of OH- in the reaction mechanism. In the given mechanism, OH- acts as a reactant in the first step and is regenerated in the second step.
2. Understand the effect of adding HCl, a strong acid, to the solution. HCl will increase the concentration of H+ ions in the solution.
3. Recognize the reaction between H+ and OH- ions. When HCl is added, H+ ions will react with OH- ions to form water, thereby decreasing the concentration of OH- ions available for the reaction.
4. Analyze how the decrease in OH- concentration affects the reaction rate. Since OH- is a reactant in the first step of the mechanism, a decrease in its concentration will slow down the rate of this step and thus the overall reaction rate.
5. Conclude that adding HCl to the solution will decrease the rate of the overall reaction due to the reduction in OH- ion concentration, which is essential for the reaction to proceed.

Key Concepts

Reaction Mechanism

A reaction mechanism describes the step-by-step sequence of elementary reactions by which overall chemical change occurs. Understanding the mechanism of nitramide decomposition is crucial, as it reveals how reactants are transformed into products and how intermediates are formed. Each step can have different rates, influencing the overall reaction rate.

Effect of pH on Reaction Rates

The pH of a solution can significantly affect the rates of chemical reactions, particularly those involving acids and bases. In this case, adding HCl will increase the concentration of H+ ions, potentially altering the equilibrium and the rate of the reaction by affecting the availability of hydroxide ions (OH-) that participate in the mechanism.

Catalysis

Catalysis involves the acceleration of a chemical reaction by a substance called a catalyst, which is not consumed in the reaction. In the context of this question, adding HCl may act as a catalyst by providing protons that can shift the reaction equilibrium or enhance the rate of the reaction, thereby influencing the overall kinetics of nitramide decomposition.