An atom has electronic configuration 2, 8, 7.
To which of the following elements would it be chemically similar? (Atomic numbers are given in parentheses).
N(7), F(9), P(15), Ar(18)

Explanation

To determine which element is chemically similar to the atom with the electronic configuration 2, 8, 7, we need to analyze the given options based on their electronic configurations and the number of valence electrons.

### Step-by-Step Solution:

1. **Identify the given electronic configuration**: The atom has an electronic configuration of 2, 8, 7. This means it has:
- 2 electrons in the first shell (K shell),
- 8 electrons in the second shell (L shell),
- 7 electrons in the third shell (M shell).
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