JEE Main 2016 · 9 Apr · Shift 1 · Chemistry Q39

ChemistrySingle correct+4 / -1Question 39 of 90

The reaction of ozone with oxygen atoms in the presence of chlorine atoms can occur by a two step process shown below :

$\ce{O3(g) + Cl^.(g) -> O2(g) + ClO^.(g)}$ ...... (i) $k_i=5.2\times10^9$ L mol $^{-1}$ s $^{-1}$

$\ce{ClO^.(g) + O^.(g) -> O2(g) + Cl^.(g)}$ ...... (ii) $k_{ii}=2.6\times10^{10}$ L mol $^{-1}$ s $^{-1}$

The closest rate constant for the overall reaction $\ce{O3(g) + O^.(g) -> 2O2(g)}$ is :

5.2\times10^9

L mol

^{-1}

^{-1}

2.6\times10^{10}

L mol

^{-1}

^{-1}

3.1\times10^{10}

L mol

^{-1}

^{-1}

1.4\times10^{20}

L mol

^{-1}

^{-1}

Answer and worked solution

Official answer: A

The overall rate is set by the slower step (i), so the effective rate constant is closest to $k_i=5.2\times10^9$ L mol⁻¹ s⁻¹.

JEE Main 2016 · 9 Apr · Shift 1, Chemistry question 39