Question

If the rate constant of a reaction has the value $k=163\times 10^{-4}(mol{)}^{-\frac{1}{2}}{s}^{-1}$, the order of the reaction is

• A. one
• B. two
• C. zero
• D. None of these

Answer 1

Answer: (D)

Rate constant, $k=1.63\times 10^{-4}(mol{)}^{-1/2}{s}^{-1}$
For nth order reaction, $k=\frac{\text{ Rate }}{(\text{ conc }{)}^n}\frac{\text{ Conc. }}{\text{ time }}\times \frac{1}{(\text{ Conc }{)}^n}$
$Sl$ units of concentration is $mol{L}^{-1}$ and time is $s$.
Therefore, the units of $k=mo{l}^{-1/2}{s}^{-1}$ cannot be possible.