English
Karnataka Board PUCPUC Science 2nd PUC Class 12

Calculate the half-life of a first order reaction from the rate constant given below: 4 year−1

Advertisements
Advertisements

Question

Calculate the half-life of a first order reaction from the rate constant given below:

4 year−1

Numerical
Advertisements

Solution

For a first-order reaction,

Half-life (t1/2) = `0.693/k`

= `0.693/4`

= 0.173 years

shaalaa.com
  Is there an error in this question or solution?
Chapter 3: Chemical Kinetics - 'NCERT TEXT-BOOK' Exercises [Page 279]

APPEARS IN

Nootan Chemistry [English] Class 12 ISC
Chapter 3 Chemical Kinetics
'NCERT TEXT-BOOK' Exercises | Q 4.13 (iii) | Page 279
NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 3 Chemical Kinetics
Exercises | Q 3.13 (iii) | Page 86

RELATED QUESTIONS

The integrated rate equation for first order reaction is A → products


Sucrose decomposes in acid solution to give glucose and fructose according to the first order rate law. The half life of the reaction is 3 hours. Calculate fraction of sucrose which will remain after 8 hours.


During nuclear explosion, one of the products is 90Sr with half-life of 28.1 years. If 1μg of 90Sr was absorbed in the bones of a newly born baby instead of calcium, how much of it will remain after 10 years and 60 years if it is not lost metabolically?


The half-life period of zero order reaction A → product is given by

(a) `([A]_0)/k`

(b) `0.693/k`

(c) `[A]_0/(2k)`

(d) `(2[A]_0)/k`


Show that the time required for 99% completion is double of the time required for the completion of 90% reaction.


Define half life of a reaction.


Show that for a first order reaction half life is independent of initial concentration.


For the first order reaction, half-life is equal to ____________.


Calculate half-life period of life order reaction whose rate constant is 200 sec–1


Half life (t1/2) and completion time (T) of the zero order reaction are- (K = 0.001 mol/litre/sec and a = 1 M.)


A first-order reaction takes 69.3 min for 50% completion. What is the time needed for 80% of the reaction to get completed? (Given: log 5 = 0.6990, log 8 = 0.9030, log 2 = 0.3010)


The half-life of cobalt 60 is 5.26 years. The percentage activity remaining after 4 years is ______%.


A reaction has a half-life of 1 min. The time required for 99.9% completion of the reaction is ______ min.
(Round off to the nearest integer).
[Use: In 2 = 0.69; In 10 = 2.3]


Obtain a relation, `k_2/k_1 = ((t_(1/2))_2)/((t_(1/2))_1)`, where k1 and k2 are rate constants while (t1/2)and  (t1/2)are half-life periods of the first order reaction at temperatures T1 and Trespectively. Write the relation for activation energy.


The unit of rate constant of zero order reaction is ______.


Show that the half-life of zero order reaction is `t_(1/2) = ([A]_0)/(2k)`.


Calculate the half-life of a first order reaction from the rate constant given below:

2 min−1


A first order reaction takes 40 min for 30% decomposition. Calculate t1/2.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×