For an endothermic reaction A → B , an activation energy of forward reaction is 15 kcal mol-1 and enthalpy change of reaction is 5 kcal mol-1. The activation energy for reverse reaction B → A is
Correct answer: A. 10 kcal mol-1
- A. 10 kcal mol-1
- B. 15 kcal mol-1
- C. 20 kcal mol-1
- D. Zero
Explanation
The activation energy for the reverse reaction B → A is 10 kcal mol^-1. The activation energy for the reverse reaction can be calculated using the following equation: Ea,rev = Ea,fwd - ΔHrxn where: Ea,rev is the activation energy for the reverse reaction Ea,fwd is the activation energy for the forward reaction ΔHrxn is the enthalpy change of reaction Plugging in the values from the question, we get: Ea,rev = 15 kcal mol-1 - 5 kcal mol-1 = 10 kcal mol-1
Last updated
About Reaction Kinetics
Reaction kinetics relates reaction rate to concentration, temperature, surface area and catalysts. Questions cover rate laws, reaction order, rate constants, activation energy and the activated complex, including how a catalyst lowers the activation energy without changing the overall energy change or equilibrium position.
Practise Reaction Kinetics
573 free Reaction Kinetics MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Exams that ask Chemistry questions like this
Chemistry is on 14 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
Related questions
100 g of a substance decays slower than 50 g of the same substance. The order of decay follows kinetics:
12.Rate of disappearance of reactant is equal to
13.Rate of reaction, when concentration of reactants are taken as unity is called
14.Order of reaction of N2O5→2N2O5+ O2
16.Which order of reaction obeys the relation t1/2= 1/Ka