Question

The process of conversion of ozone into oxygen $\left(2O_{3} \longrightarrow 3O_{2}\right)$ involves following steps $O _{3} {<=>[{\text { Fast }}]} O _{2}+ O$ $O + O _{3} {->[{\text { Slow }}]} 2 O _{2}$ The rate law expression for this process is

• A. $ r=k{{[{{O}_{3}}]}^{2}} $
• B. $ r=k{{[{{O}_{3}}]}^{2}}{{[{{O}_{2}}]}^{-1}} $
• C. $ r=k[{{O}_{3}}][{{O}_{2}}] $
• D. $ r=k{{[{{O}_{3}}]}^{2}}{{[{{O}_{2}}]}^{-3}} $

Answer 1

The Correct Option is B

$O _{3} {<=>[{\text { Fast }}]} O _{2}+ O$
$O + O _{3} {->[{\text { Slow }}]} 2 O _{2}$
From equation (i)
$K_{c}=\frac{\left[ O _{2}\right][ O ]}{\left[ O _{3}\right]}$
or $[ O ] =\frac{K_{ c }\left[ O _{3}\right]}{\left[ O _{2}\right]} $
Rate $=k\left[ O _{3}\right][ O ]$
$=k\left[ O _{3}\right] . \frac{K_{c}\left[ O _{3}\right]}{\left[ O _{2}\right]} $
$=k^{'}\left[ O _{3}\right]^{2}\left[ O _{2}\right]^{-1}$