GATE 2023 MT – Question 34
A reaction’s rate constant at 400 K is three times that at 300 K. Its activation energy is ______ kJ mol$^{-1}$ (one decimal place). Given: $R=8.314$ J mol$^{-1}$ K$^{-1}$.
Practise this question in The GATE Grind →
Show answer and explanation
Correct answer: 10.5 to 11.5
Explanation
Arrhenius gives $\ln(k_{400}/k_{300})=(E_a/R)(1/300-1/400)$.
Therefore $E_a=8.314\ln3/(1/300-1/400)=10960.65$ J/mol, or **11.0 kJ/mol**.