The half life of `._38Sr^(90)` is 28 years. What is disintegration rate of 15g of this isotope?

Explanation

To find the disintegration rate of 15g of the isotope \( _{38}^{90}\text{Sr} \), we will follow these steps:

### Step 1: Calculate the number of nuclei (n) in 15g of \( _{38}^{90}\text{Sr} \)

The number of nuclei can be calculated using Avogadro's number and the molar mass of the isotope.

\[
n = \frac{N_A \cdot m}{M}
...