Why does the rate of a reaction not remain constant throughtout the reaction?

Explanation

**Step-by-Step Solution:**

1. **Understanding Reaction Rate**: The rate of a reaction is defined as the change in concentration of reactants or products per unit time. It quantifies how fast a reactant is consumed or how fast a product is formed.

2. **Dependence on Concentration**: The rate of a reaction depends on the molar concentrations of the reactants. As the reaction proceeds, the concentrations of the reactants decrease while the concentrations of the products increase.

3. **Non-uniform Change in Concentration**: The change in concentration of reactants and products is not uniform throughout the reaction. Initially, when the concentrations of reactants are high, the rate of reaction is generally faster. As the reactants are consumed, their concentrations decrease, leading to a slower rate of reaction.

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