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Academic session 2026-27, Chapter 3 in the current curriculum.
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 17:
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.
. 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.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.

Therefore, 0.7814 μg of 90Sr will remain after 10 years.
Again,

Therefore, 0.2278 μg of 90Sr will remain after 60 Years
The reaction between A and B is first order with respect to A and zero order with respect to B. Fill in the blanks in the following table:
| Experiment |
A/ mol L - 1 |
B/ mol L - 1 |
Initial rate/mol L - 1 min - 1 |
| I | 0.1 | 0.1 |
2.0 × 10 - 2 |
| II | -- | 0.2 |
4.0 × 10 - 2 |
| III | 0.4 | 0.4 | -- |
| IV | -- | 0.2 |
2.0 × 10 - 2 |
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:
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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 17: During nuclear explosion, one of the products is 90Sr with half-life of 28.1 years. If 1μg of 90S....
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Comments
cos its radioactive
How do we know it is a first order reaction?
Nicely explained it
Thanks a lot for this And it's really a wonderful site
thank you
thank you
Thank you so very much - the chemistry and biology solutions are very comprehensive, and easy to understand. I really appreciate the efforts taken by the site's creators.