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The first-order disappearance of a subst...

The first-order disappearance of a substance has a half-life of `34.0` s. How long does it take for the concentration of that substance to fall to `12.5%` of its initial value?

A

11 s

B

68 s

C

102 s

D

272 s

Text Solution

Verified by Experts

The correct Answer is:
C
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GRB PUBLICATION-CHEMICAL KINETICS-C. Integrated Rate Laws
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  4. For a first order chemical reaction : A rarr P. The correct statement(...

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  5. Which does not change with time for a first-order reaction?

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  7. Which statement about second order reactions is correct?

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  8. For the reaction A rarr B that is first-order in A, The rate constant ...

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  9. A substance, X, undergoes a first order reaction XrarrY with a half li...

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  10. For reaction, A rarr B, the rate law is rate = k[A]. If the reaction i...

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  11. What is the half life of the irreversible first order reaction, A rarr...

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  12. The first-order disappearance of a substance has a half-life of 34.0 s...

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  14. Which change will decrease the rate of the reaction between I(2)(s) an...

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  15. What is the first-order rate constant for the reaction that is 36.5% c...

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  16. The half-life of a first-order reaction is 1.5 hours. How much time is...

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  17. What are the units for the rate constant of a zero-order reaction?

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  18. For a first order reaction A rarr B, find [(t(7//8))/(t(1//2))].

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  19. For the zero order reaction : A rarr P, K=10^(-2)("mol"//"litre")sec...

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  20. Which is constant for different reactant concentrations in a first-ord...

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