Question

protons: 8
neutrons: 9
electrons: 10
what is the mass number?

Explanation:

Step1: Recall the formula for mass number

The mass number \(A\) of an atom is given by the sum of the number of protons \(p\) and neutrons \(n\), i.e., \(A=p + n\).

Step2: Substitute the given values

Here, \(p = 8\) and \(n=9\). So, \(A=8 + 9\).

Step3: Calculate the sum

\(8+9 = 17\).

Answer:

\(17\)