Nucleus: Practice Problem & Solution

Solution Explained:

To solve this problem, we apply the core principles of Nucleus. Understanding the underlying formula is key to arriving at the correct answer below:

For a nucleus represented as $ _{Z}X^{A} $, the number of protons is $ Z = 11 $. The number of neutrons is $ A - Z = 23 - 11 = 12 $. Since it is a nucleus, there are no electrons present, so electrons = 0.