Question

Reaction of chloroform with chlorine is an example of fraction order reaction. Its rate law expression is rate $=k\left[CHC{l}_3\right]{\left[C{l}_2\right]}^{1/2}$. If both are assumed in gaseous state and pressure is measured in bar then units of rate and rate constant respectively are

• A. bar ${\min }^{-1}$, bar ${}^2{\min }^{-1}$
• B. bar ${\min }^{-1},{\text{bar}}^{-1/2},{\min }^{-1}$
• C. ${\text{bar}}^{-1/2},{\min }^{-1},{\text{bar}}^2{\min }^{-1}$
• D. bar ${\min }^{-1}$, bar ${}^{-1/2}{\min }^{-1}$

Answer 1

Answer: (B), (D)

Given, rate $=k\left[CHC{l}_3\right]{\left[C{l}_2\right]}^{1/2}$
Order $=1+\frac{1}{2}=\frac{3}{2}$
So, units of rate constant $=\frac{\text{ Units of rate }}{\left[CHC{l}_3\right]{\left[C{l}_2\right]}^{1/2}}=\frac{{\text{bar min}}^{-1}}{{\text{bar}}^{3/2}}$
Units of rate is bar ${\min }^{-1}$.