If the rate of reaction X → Y increases fourfold upon doubling the concentration of ‘X’ and follows the rate law r = K * Cx n, what is the value of ‘n’_______________________?
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Answer: C. 2
Explanation
A fourfold increase in reaction rate upon doubling reactant concentration indicates a squared concentration dependence. Substituting these experimental values into the rate law yields two to the power n equals four. Solving this exponential equation confirms that the reaction order n must be equal to two. Second order reactions feature reaction rates proportional to the square of a single reactant concentration. Doubling reactant concentrations in second order systems quadruples the frequency of effective bimolecular collisions. Empirical rate law determinations rely on observing how rate changes correspond to concentration adjustments.
Gas phase bimolecular reactions frequently follow second order kinetics governed by collision theory. Industrial reactor sizing for second order reactions requires accounting for rapid initial consumption rates. Kinetic data analysis in chemical laboratories often uses logarithmic plots to extract reaction orders. Option A suggests zero order, where doubling concentration would produce no change in the reaction rate. Option B proposes first order, where doubling concentration would only result in a twofold rate increase. Option D implies a third order reaction, which would cause an eightfold rate increase upon concentration doubling.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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