Consider the reaction H₂(g) + I₂(g) → 2 HI(g). The reaction of a fixed amount of H₂ and I₂ is studied in a cylinder fitted with a movable piston. Indicate the effect of each of the following changes on the rate of the reaction. (c) The addition of a catalyst

Verified step by step guidance

1. Identify the role of a catalyst in a chemical reaction: A catalyst provides an alternative reaction pathway with a lower activation energy.
2. Understand that the activation energy is the minimum energy required for a reaction to occur. Lowering this energy increases the number of effective collisions between reactant molecules.
3. Recognize that by lowering the activation energy, a catalyst increases the rate of the reaction without being consumed in the process.
4. Note that the presence of a catalyst does not affect the equilibrium position of the reaction; it only helps the system reach equilibrium faster.
5. Conclude that the addition of a catalyst will increase the rate of the reaction by providing a more efficient pathway for the reaction to proceed.

Key Concepts

Catalysts

A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process. It works by providing an alternative reaction pathway with a lower activation energy, allowing more reactant molecules to collide with sufficient energy to react. This means that even at lower temperatures, reactions can proceed more quickly when a catalyst is present.

Reaction Rate

The reaction rate refers to the speed at which reactants are converted into products in a chemical reaction. It can be influenced by several factors, including concentration, temperature, and the presence of a catalyst. Understanding how these factors affect the reaction rate is crucial for predicting how changes in conditions will impact the overall progress of a reaction.

Equilibrium and Dynamic Processes

In a chemical reaction, equilibrium is reached when the rate of the forward reaction equals the rate of the reverse reaction, resulting in constant concentrations of reactants and products. The addition of a catalyst does not change the position of equilibrium; it only accelerates the time taken to reach that equilibrium. This concept is essential for understanding how catalysts influence reaction kinetics without altering the final outcome.