A chemical reaction has a half-life period proportional to CA0 -1 if its order is _______________?
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Answer: C. Second
Explanation
Second-order reaction half-lives are inversely proportional to the initial reactant concentration. Doubling initial concentration cuts the second-order half-life period precisely in half. Integrating second-order rate equations naturally introduces initial concentration into denominator terms. Reaction order determines the mathematical dependence of half-life on initial reactant concentrations. Second-order reactions involve two reacting species or the bimolecular reaction of a single species. Kinetic data analysis uses half-life trends across varying concentrations to determine reaction orders.
Polymerization reactions often follow second-order kinetics requiring careful concentration control. Industrial reactor sizing for second-order reactions must account for varying half-life durations. Wastewater treatment kinetics frequently exhibit second-order concentration dependencies. First-order reactions have half-lives that are completely independent of initial concentrations. Zero-order reactions have half-lives that are directly proportional to initial concentrations. Third-order reactions exhibit inverse square dependence on initial reactant concentrations.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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