CUET · CHEMISTRY · PYQ PAPER 2025
A first order reaction is found to have a rate constant, k = 5.5 × 10-14 s-1. The half life of the reaction will be :
- A 1.26 x 1011 s
- B 1.26 × 1013 s
- C 1.26 × 1019 s
- D 1.86 × 1011 s
Answer & Solution
Correct Answer
(B) 1.26 × 1013 s
Step-by-step Solution
Detailed explanation
\( t_{1/2} = \frac{0.693}{k} \) \( t_{1/2} = \frac{0.693}{5.5 \times 10^{-14} \text{ s}^{-1}} \) \( t_{1/2} = 1.26 \times 10^{13} \text{ s} \)
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