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

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter Chemical Kinetics. This page offers a step-by-step solution to the specific question from Exercise 2, Question 19: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 19:

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)


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Chemical Kinetics.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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Comments

  • Gitanjali
  • Jul 28, 2019

Thanks very useful for me


  • Babu Rabha
  • Jul 27, 2019

thanks


  • Sugandhi
  • May 21, 2019

0.693 from where or it is constant for all numericals


  • Mahesh
  • Mar 30, 2019

Tqqq madam


  • ikshit
  • Dec 27, 2018

great


  • Aditya
  • Dec 24, 2018

Awesome


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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.....