Concept:Standard kinetic theory states that a rate constant typically doubles for every 10°C rise. However, examiners sometimes mistakenly apply a simplistic linear multiplier instead of an exponential one.
Solution:- Scientific Reality: A 50°C increase equals five 10-degree intervals. The rate should increase by \( 2^5 = 32 \) times, yielding \( 96 \times 10^{-12} \). This is not an option.
- Exam Logic (Flawed but Required): The paper setter incorrectly assumed a linear proportionality.
- Temperature difference: \( 250^\circ\text{C} - 200^\circ\text{C} = 50^\circ\text{C} \).
- Number of 10-degree intervals: \( 50 / 10 = 5 \).
- The setter simply multiplied the base rate constant by the number of intervals: \( 5 \times (3 \times 10^{-12}) = 15 \times 10^{-12} \).
- Therefore, following the examiner's flawed mathematical intent, the answer is D.
Why other options are incorrect:While chemically inaccurate, options A, B, and C do not even align with the linear miscalculation model utilized by the examiner to generate the official key.
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