If the pre-exponential factor in Arrhenius equation is 1.6 × 1012 s-1 , the value of rate constant at extremely high temperature will be close to

Question

If the pre-exponential factor in Arrhenius equation is 1.6 × 1012 s-1 , the value of rate constant at extremely high temperature will be close to (A)  4.2 × 1012 s-1  (B) 1.6 ×012 s-1  (C) 2.4 × 1012 s-1  (D) 1.2 × 106 s-1

Tardigrade Admin · Accepted Answer

k=Ae - (Ea/RT) At extremely high temperature T → ∞ ∴ k =Ae (Ea/R∞) ⇒ k = Ae-0 ⇒ k = (A/e0) ⇒ k=A

Q. If the pre-exponential factor in Arrhenius equation is $1.6 \times 1 0^{12} s^{- 1}$ , the value of rate constant at extremely high temperature will be close to

$4.2 \times 1 0^{12} s^{- 1}$

$1.6 \times 0^{1} 2 s^{- 1}$

$2.4 \times 1 0^{12} s^{- 1}$

$1.2 \times 1 0^{6} s^{- 1}$

$k = A e - \frac{E _{a}}{RT}$
At extremely high temperature $T \to \infty$
$∴ k = A e \frac{E _{a}}{R ^{\infty}} \Rightarrow k = A e^{- 0} \Rightarrow k = \frac{A}{e ^{0}} < b r / >\Rightarrow k = A$

Q. If the pre-exponential factor in Arrhenius equation is 1.6×1012s−1, the value of rate constant at extremely high temperature will be close to

4.2×1012s−1

1.6×012s−1

2.4×1012s−1

1.2×106s−1