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Solve the following.
The data given below is for the reaction between [NO] and [ ] to form NOCl at . S.No. Conc. of [NO]…
The data given below is for the reaction between [NO] and [$\text{Cl}_2$] to form NOCl at $25^\circ\text{C}$.
Find the value of rate constant ($k$).
| S.No. | Conc. of [NO] mol $\text{L}^{-1}$ | Conc. of [$\text{Cl}_2$] mol $\text{L}^{-1}$ | Rate: mol $\text{L}^{-1}\text{ sec}^{-1}$ |
|---|---|---|---|
| 1. | 2.0 | 2.0 | $2.0 \times 10^{-3}$ |
| 2. | 2.0 | 6.0 | $6.0 \times 10^{-3}$ |
| 3. | 6.0 | 2.0 | $1.8 \times 10^{-2}$ |
Answer
Answer
AIRate $= k[\text{NO}]^2[\text{Cl}_2]$. From experiment 1:
$k = \dfrac{2.0\times10^{-3}\text{ mol L}^{-1}\text{ s}^{-1}}{(2.0\text{ mol L}^{-1})^2(2.0\text{ mol L}^{-1})} = 2.5\times10^{-4}\text{ L}^2\text{ mol}^{-2}\text{ s}^{-1}$
Experiments 2 and 3 give the same value.
Final answer: $2.5\times10^{-4}$ L^2 mol^-2 s^-1
From ISC 2025 Chemistry Paper 1, question 18(iii).
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