An atom has electronic configuration 2, 8, 7.
What is the atomic number of this element?

Explanation

To find the atomic number of the element with the electronic configuration 2, 8, 7, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Electronic Configuration**: The electronic configuration of an atom describes the distribution of electrons in its atomic orbitals. In this case, the configuration is given as 2, 8, 7.

2. **Calculate Total Electrons**:
- The first shell can hold 2 electrons.
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