Chemistry · 2025
JEE Main · 7 April 2025, Shift 2 · Q57
A ( g ) → B ( g )+ C ( g ) is a first order reaction. The reaction was started with reactant A only. Which of the following expression is correct for…
$\displaystyle \mathrm{A}(\mathrm{g}) \rightarrow \mathrm{B}(\mathrm{g})+\mathrm{C}(\mathrm{g})$ is a first order reaction.
The reaction was started with reactant A only. Which of the following expression is correct for rate constant k ?
| Time | t | $\displaystyle \infty$ |
| $\displaystyle \mathrm{p}_{\text {system }}$ | $\displaystyle \mathrm{p}_{\mathrm{t}}$ | $\displaystyle \mathrm{p}_{\infty}$ |
Official answer
From NTA’s final answer key for this paper.
(2)
$\displaystyle k=\frac{1}{t} \ln \frac{p_{\infty}}{2\left(p_{\infty}-p_t\right)}$
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JEE Main 2025 Chemistry question, with the answer from NTA’s final answer key. Where our answers come from.