Question

For a homogeneous reaction of order n, the unit of rate constant, k is ____

(a) conc^n-1

(b) \(\frac{conc^{-1}}{time} \)

(c) \(\frac{conc^{-1}}{time^{1-n}} \)

(d) \(\frac{conc^{1-n}}{time^{-1}} \)

I had been asked this question in examination.

Enquiry is from Reaction Rates topic in portion Basic Concepts of Chemical Reaction Engineering

Answer 1

Correct option is (d) \(\frac{conc^{1-n}}{time^{-1}} \)

To explain I would say: For any order n, (-rA) = kCA^n

\(\frac{mol}{m^3×s} = k.(\frac{mol}{m^3})^n \)

Hence the unit of k is \(\frac{conc^{1-n}}{time^{-1}}. \)