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CBSE Class 11-science Answered

In 12.4 hours, a 100 gram sample of an element decays so that its mass is 25 grams. grams. What is the approximate half-life of this radioactive substance? 
Asked by tv2000in | 30 Mar, 2019, 10:31: AM
Expert Answer
Initial mass = 100 gm
 
After one half-life, mass of decayed element = 50 gm
 
after two half-life mass of decayed element = 25 gm
 
hence 12.4 hours is two half-life or one half-life = 6.2 hours
Answered by Thiyagarajan K | 30 Mar, 2019, 02:45: PM

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