Consider the Arrhenius equation given below and mark the correct option.
$k = A . e - \frac{E_{a}}{R T}$
(a) Rate constant increases exponentially with increasing activation energy and decreasing temperature
(b) Rate constant decreases exponentially with increasing activation energy and decreasing temperature
(c) Rate constant increases exponentially with decreasing activation energy and decreasing temperature
(d) Rate constant increases exponentially with decreasing activation energy and increasing temperature

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Solution

Answer: (d) Rate constant increases exponentially with decreasing activation energy and increasing temperature

According to Arrhenius equation $A e^{-} E_{a} / R T$

$l n k = l n (A e^{\frac{- E_{a}}{R T}})$
$l n k = l n A + l n (e^{\frac{- E_{a}}{R T}})$
$l n k = l n A + l n (e^{\frac{- E_{a}}{R T}})$
$l n k = l n A - \frac{E_{a}}{R T}$
From the above equation, $K α \frac{1}{E_{a}}$ and $K α T$

which indicates that as activation energy decreases rate constant increases and as temperature increases the rate of reaction increases.

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Similar questions

Which of the following statements are in accordance with the Arrhenius equation?
(a) Rate of a reaction increases with increase in temperature
(b) Rate of a reaction increases with a decrease in activation energy
(c) Rate constant decreases exponentially with an increase in temperature
(d) Rate of reaction decreases with a decrease in activation energy

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k = A e^{- \frac{E_{a}}{R T}}

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