For the 1st order decomposition reacton 2N2O5(g) → 2N2O4(g) + O2(g) the half-life is given as
Correct answer: A. 0.693/k
- A. 0.693/k
- B. log 2/k
- C. 0.693/2k
- D. In2/k
Explanation
Rate equation for the above reaction is Rate = k[N2O5] Since it is a first order reaction, ∴ t1/2 ∝ 1 / k (where t1/2 is half life and k is the rate constant) t1/2 = c / k (where c is a constant number which is ln2 = 0.693) ∴ t1/2 = 0.693 / k
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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.
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