JEE Mains · Chemistry · STD 12 - 3. Chemical kinetics
A molecule undergoes two independent first order reactions whose respective half lives are \(12\,min\) and \(3\,min\). If both the reactions are occurring then the time taken for the \(50 \%\) consumption of the reactant is \(..........\,\min\) (Nearest integer)
- A \(4\)
- B \(2\)
- C \(6\)
- D \(8\)
Answer & Solution
Correct Answer
(B) \(2\)
Step-by-step Solution
Detailed explanation
\(\frac{1}{t_{1 / 2}}=\frac{1}{3}+\frac{1}{12}=\frac{4+1}{12}=\frac{5}{12}\) \(t_{1 / 2}=\frac{12}{5} min =2.4\) \(\approx 2\)
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