A first order reaction takes 40 min for | Class 12 Chemistry Chapter Chemical Kinetics, Chemical Kinetics NCERT Solutions

Question:

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

Answer:

For a first order reaction,

t = 2.303/k Log [R] º / [R]

k = 2.303/40min  Log 100 / 100-30

= 2.303/40min  Log 10 / 7

= 8.918 x 10-3 min-1

Therefore, t1/2 of the decomposition reaction is

t1/2 = 0.693/k

0.693 / 8.918 x 10-3  min

= 77.7 min (approximately)


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Comments

  • Gitanjali
  • 2019-07-28 21:40:03

Thanks very useful for me


  • Babu Rabha
  • 2019-07-27 20:53:58

thanks


  • Sugandhi
  • 2019-05-21 20:12:03

0.693 from where or it is constant for all numericals


  • Mahesh
  • 2019-03-30 19:13:41

Tqqq madam


  • ikshit
  • 2018-12-27 13:01:45

great


  • Aditya
  • 2018-12-24 01:47:15

Awesome


Comment(s) on this Question

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 2 , Question 19: A first order reaction takes 40 min for 30% decomposition. Calculate t1/2.....