Chemical Kinetics Question 30
Question: The rate law for a reaction between the substances A and B is given by, rate $ =k{{[A]}^{n}}{{[B]}^{m}} $ . On doubling the concentration of A and halving the concentration of B, the ratio of the new rate to the earlier rate of the reaction will be as [AIEEE 2003]
Options:
A) $ \frac{1}{{2^{(m+n)}}} $
B) $ (m+n) $
C) $ (n-m) $
D) $ {2^{(n-m)}} $
Show Answer
Answer:
Correct Answer: D
Solution:
$ R=K{{(A)}^{n}}{{(B)}^{m}} $
$ R’=K{{(2A)}^{n}}{{( \frac{B}{2} )}^{m}} $
$ =K{{(A)}^{n}}2^{n}{{(B)}^{m}}{2^{-m}} $
$ =K{{(A)}^{n}}{{(B)}^{m}}{2^{n-m}} $ , $ \frac{R’}{R}=\frac{K{{(A)}^{n}}{{(B)}^{m}}{2^{n-m}}}{K{{(A)}^{n}}{{(B)}^{m}}}={2^{n-m}} $
