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Compounds A and B react with a common re...

Compounds A and B react with a common reagent with first order kinetics in both cases. If 99% of A must react before 1% of B has reacted, what is the minimum ratio for their respective rate constants ?

A

916

B

229

C

500

D

458

Text Solution

Verified by Experts

The correct Answer is:
D
The fraction of A and B remaining at time t when 99% of A has reacted, are (A=0.01, B=0.99)
`k_A=1/t` In 100 and `k_B=1/t` In `100/99`
`:. K_A/k_B=(ln 100)/(ln[100//99])=458`
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