Magnesium-28 decays by β emission to give aluminum-28. If yellow spheres represent
Interpretation:
The number of half-lives when
Concept Introduction:
Half-life:
The time required to reduce a radioactive isotope to half of its initial value.
Explanation of Solution
Figure 1
From the above figure,
We know that, yellow spheres are representing
The total number of yellow spheres present in first box is
The number of yellow spheres present in second box after beta decay is 4
So, the number of half-lives needed is
The number of half-lives when
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