Question

An element $A$ belongs to IIA group and another element $B$ belongs to VIA group. The compound formed between $A$ and $B$ contains:

• A. $A^{++},B^{-}$ ions
• B. $A^{++},B^{--}$ ions
• C. $A^{--},B^{++}$ ions
• D. $A^{+},B^{--}$ ions

Answer 1

The correct option is B $A^{++},B^{--}$ ions

An element of group IIA has two electrons in the outermost shell which it can lose to achieve inert gas configuration. Hence, its valency is 2. It forms $A^{2+}$ions.

An element of group VIA has 6 electrons in its outermost shell. It needs two more electrons to attain inert gas configuration. Hence its valency is 2. It forms $B^{2-}$ions.

A compound formed between them is $AB$

$A^{2+}{B}^{2-}$
$A^{++}{B}^{--}$