Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
The rate constant of a reaction is given by $k=P Z e^{-E_{a} / R T}$ under standard notation. In order to speed up the reaction, which of the following factors has to be decreased?
ChemistryChemical KineticsKCETKCET 2020
Options:
  • A $Z$
  • B Both $Z$ and $T$
  • C $E_{a}$
  • D $T$
Solution:
1683 Upvotes Verified Answer
The correct answer is: $E_{a}$
$\therefore k=P Z e^{-E a / R T}$
The above reaction expression is given in terms of exponents. We have to increase the speed of reaction. So, value of $k$ has to be more and as per the given expression.
$k \propto \frac{1}{e^{E_{a} / R T}}$
if $E a$ decreases, than $\left[e^{E_{a} / R T}\right]$ also decreases and $\left[e^{\frac{1}{E_{a} / R T}}\right]$ increases.
$\therefore k$ also increases

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.