Q24 / 100 · BITSAT 2024 (Memory Based Paper 3) · Chemistry
If for a first order reaction, the value of $A$ and $E_a$ are $4 \times 10^{13} \mathrm{~s}^{-1}$ and $98.6 \mathrm{~kJ} \mathrm{~mol}^{-1}$
respectively, then at what temperature will its half life period be 10 minutes?
- A330 K
- B300 K
- C330.95 K
- Correct answerD311.15 K
Solution
According to Arrhenius equation,
$\log k=\log A-\frac{E_a}{2.303 R T}...(i)$
For $1^{\text {st }}$ order reaction,
$k=\frac{0.693}{t_{1 / 2}}=\frac{0.693}{600 s}=1.1 \times 10^{-3} \mathrm{~s}^{-1}$
Substitute the value of $k$ in Eq. (i)
$log \left(1.1 \times 10^{-3}\right)=\log \left(4 \times 10^{13}\right)-\frac{98.6 \times 10^3}{2.303 \times 8.314 \times T}$
Solving for $T$,
$T=311.15 \mathrm{~K}$
Hence, the correct answer is option: 'D'.