Question

An atom $A$ has $3$ electrons in its outermost shell and another atom $B$ has $7$ electrons in its outermost shell. What is the correct formula for their compound?

• A. $A{B}_3$
• B. $A_{3}B$
• C. $AB$
• D. Bond formation is not possible.

Answer 1

The correct option is A $A{B}_3$

An atom A has 3 electrons in its outermost shell and another atom B has 7 electrons in its outermost shell. AB${}_3$ can the correct formula for their compound. A can lose 3 electrons to form A${}^{3+}$ cation. B can gain one electron to form B${}^{-}$ anion.

Hence, the correct option is $A$