Concept:According to the Law of Mass Action, the rate of a chemical reaction is directly proportional to the active masses (concentrations) of the reacting substances.
Formula:$$ \text{Rate} \propto [\text{Reactants}]^{n} $$
Solution:- As the reaction proceeds in the forward direction, reactants are continuously consumed to form products.
- Consequently, the concentration of reactants decreases steadily.
- Since the rate is directly dependent on reactant concentration, it also decreases with the passage of time.
Why other options are incorrect:The concentration of products increases (not decreases) over time. The order of the reaction is a constant experimental value and does not change over time. Temperature is typically kept constant unless specified otherwise.
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