An atom having atomic mass number 13 has 7 neutrons. What is the atomic number of the atom.

Explanation

To find the atomic number of the atom with an atomic mass number of 13 and 7 neutrons, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definitions**:
- The **mass number (A)** of an atom is the total number of protons and neutrons in the nucleus.
- The **atomic number (Z)** is the number of protons in the nucleus of an atom.

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