Question

question 13 of 25
a sample contains 16 g of a radioactive isotope. how much radioactive
isotope remains in the sample after 1 half - life?

a. 4g
b. 16g
c. 2g
d. 8g

Explanation:

Step1: Recall the half - life concept

The amount of a radioactive isotope remaining after \(n\) half - lives is given by the formula \(N = N_0\times(\frac{1}{2})^n\), where \(N_0\) is the initial amount and \(n\) is the number of half - lives.

Step2: Substitute the values

Here, \(N_0=16\space g\) and \(n = 1\). So, \(N=16\times(\frac{1}{2})^1\).

$$N = 16\times\frac{1}{2}$$

$$N=8\space g$$

Answer:

D. \(8\space g\)