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A sample of a radioactive isotope decays from 23.9 grams to 1.49 grams in the span of 26.0 minutes What is the half life of this radioactive isotope?

User Pxm
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1 Answer

6 votes

Answer:

Half life = 6.5 min

Step-by-step explanation:

Given data:

Total amount of isotope = 23.9 g

Amount left = 1.49 g

Time taken = 26 min

Half life of isotope = ?

Solution:

First of all we will count total number of half lives taken.

At time 0 = 23.9 g

At 1st half life = 23.9 g/2 = 11.95 g

At 2nd half life = 11.95 g/2 = 5.97 g

At 3rd half life = 5.975 g /2 = 2.98 g

At 4th half life = 2.9875 g/2 = 1.49 g

Half life:

Half life = Time elapsed/ number of half lives

Half life = 26 min/ 4

Half life = 6.5 min

User Bricky
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