Chapter SH, Problem 16.3APP

To determine

To calculate: Percentage of protons in iodine-127 nucleus.

Answer to Problem 16.3APP

Percentage of protons in the nucleus is 41.7%.

Explanation of Solution

Given:

Mass number = $127$

Number of neutrons = $74$

Formula used:

Mass number is given by,

  $\text{Mass number = number of protons + number of neutrons}$

Calculation:

Number of protons is calculated as:

  $\begin{array}{l}\text{Mass number = number of protons + number of neutrons}\\ \text{Number of protons = mass number }-\text{ number of neutrons}\\ \text{Number of protons = 127}-74\\ \text{Number of protons = 53}\end{array}$

Percentage of protons in the nucleus is calculated as:

  $\begin{array}{l}\frac{\text{Number of protons}}{\text{Mass number}}\times 100\\ =\frac{53}{127}\times 100\\ =41.7\%\end{array}$

Conclusion:

Percentage of protons in the nucleus is 41.7%.