Question

consider the isotope notation shown.
\\(\ce{^{45}_{21}sc}\\)
how many protons are in the
particle?
21
19
45
24

Explanation:

Step1: Recall isotope notation

In isotope notation \(\ce{_Z^A X}\), \(Z\) is the atomic number, which equals the number of protons.

Step2: Identify \(Z\) for \(\ce{_{21}^{45}Sc}\)

For \(\ce{_{21}^{45}Sc}\), the atomic number \(Z = 21\), so the number of protons is 21.

Answer:

21 (corresponding to the option "21")