Question

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)

• A. N$\left(7\right)$
• B. F$\left(9\right)$
• C. P$\left(15\right)$
• D. Ar$\left(18\right)$

Answer 1

The correct option is B F$\left(9\right)$

The electronic configuration of F is $2,7$. The outermost shell of both chlorine and fluorine has $7$ electrons. Therefore, they are chemically similar.