Consider the following data for the given reaction $2 \mathrm{HI}_{(\mathrm{g})} \rightarrow \mathrm{H}_{2(\mathrm{~g})}+\mathrm{I}_{2(\mathrm{~g})}$ | | 1 | 2 | 3 | |---|---|---|---| | $\mathrm{HI}\left(\mathrm{mol} \mathrm{L}^{-1}\right)$ | 0.005 | 0.01 | 0.02 | | Rate $\left(\mathrm{mol} \mathrm{L}^{-1} \mathrm{~s}^{-1}\right)$ | $7.5 \times 10^{-4}$ | $3.0 \times 10^{-3}$ | $1.2 \times 10^{-2}$ | The order of the reaction is ______.

JEE Main · 2024 · 27 Jan 2024 · Shift 1 · Chemical Kinetics

Consider the following data for the given reaction

2 HI_{(g)} \to H_{2 (g)} + I_{2 (g)}

	1	2	3
$HI (mol L^{- 1})$	0.005	0.01	0.02
Rate $(mol L^{- 1} s^{- 1})$	$7.5 \times 1 0^{- 4}$	$3.0 \times 1 0^{- 3}$	$1.2 \times 1 0^{- 2}$

The order of the reaction is ______.

Answer: 2

Assume

Rate = k [HI]^{n}

. Comparing experiments 1 and 2:

\frac{3.0 \times 1 0 ^{- 3}}{7.5 \times 1 0 ^{- 4}} = (\frac{0.01}{0.005})^{n} \Rightarrow 4 = 2^{n} \Rightarrow n = 2

Experiments 2 and 3 give the same ratio (4) for the same concentration ratio (2), confirming

n = 2

JEE Main · 2024 · 27 Jan 2024 · Shift 1 · Integer answer