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What is the central idea of the Arrhenius equation k = A e^(-Ea/RT)?
ARate constant decreases as temperature rises
BRate constant rises with temperature and lower Ea
CActivation energy increases with temperature
DThe frequency factor depends strongly on temperature
Answer & Solution
Correct answer: B. Rate constant rises with temperature and lower Ea
1. The term $e^{-E_a/RT}$ is the fraction of molecules with energy above $E_a$.
2. Raising T or lowering $E_a$ makes this fraction larger.
3. So k increases with rising temperature and with lower activation energy.
4. A is essentially constant, so option D is wrong; option A reverses the trend.
_Source: NCERT Class 12 Chemistry Ch 3 "Chemical Kinetics", p.18_
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