Question

An element $M$ has an atomic mass $19$ and atomic number $9$. Its ion is represented by

• A. $M^{+}$
• B. $M^{-}$
• C. $M^{2+}$
• D. $M^{2-}$

Answer 1

The correct option is B $M^{-}$

Electronic configuration of M is $2,7$. It can accept an accept in order to have stable configuration. So ion is represented by $M^{-}$.