‹ Back to the paper
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 $25^\circ\text{C}$.
What is the order of reaction with regard to NO and $\text{Cl}_2$?
| 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
AILet rate $= k[\text{NO}]^x[\text{Cl}_2]^y$.
Experiments 1 and 2 ($[\text{NO}]$ constant): $[\text{Cl}_2]$ becomes 3 times and the rate becomes $3$ times, so $y = 1$.
Experiments 1 and 3 ($[\text{Cl}_2]$ constant): $[\text{NO}]$ becomes 3 times and the rate becomes $9$ times, so $x = 2$.
Order with respect to NO is 2 and with respect to $\text{Cl}_2$ is 1.
From ISC 2025 Chemistry Paper 1, question 18(i).