Moderate

The specific rate constant of a first order reaction depends on the

Correct answer: C. Temperature

  • A. Time
  • B. (b) Concentration of the reactant
  • C. Temperature
  • D. (d) Concentration of the product.

Explanation

Types of rates of reaction)The correct answer for the factor influencing the specific rate constant of a first-order reaction is:(c) TemperatureHere's why the other options are incorrect:(a) Time: Time itself does not affect the specific rate constant, which is an intrinsic property of the reaction and reflects its inherent speed. The rate of a first-order reaction does decrease with time as the reactant concentration depletes, but this is due to changing reactant concentration, not time itself.(b) Concentration of the reactant: While the rate of a first-order reaction is directly proportional to the reactant concentration, this does not affect the specific rate constant. The constant represents the rate at which the reaction proceeds when the reactant concentration is 1 M.(d) Concentration of the product: The concentration of the product has no direct influence on the rate of a first-order reaction. This is because the rate is solely dependent on the concentration of the reactant in a first-order process.Therefore, temperature is the only factor that directly influences the specific rate constant of a first-order reaction. According to the Arrhenius equation, the rate constant increases exponentially with increasing temperature due to the increased kinetic energy of molecules and easier overcoming of the activation energy barrier.

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About Reaction Kinetics

Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.

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