alleryArrhenius equation: k = A × e^(-Ea/RT). What is A?
AActivation energy
BPre-exponential or 'frequency' factor
CEquilibrium constant
DTemperature
Answer & Solution
Correct answer: B. Pre-exponential or 'frequency' factor
A is the frequency factor (or Arrhenius prefactor): accounts for collision frequency and orientation. Has same units as k.
Often only weakly T-dependent compared to exp term.
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