Question

There is a tendency for elements of groups 13 to 15 of higher periods, particularly 6, to form compounds with ions having a positive charge of_____ less than the group number.

• A. one
• B. three
• C. four
• D. two

Answer 1

The correct option is D two

$\begin{array}{c}\text{There exist}T{l}^{+1}3-1=23=\text{group number.}\\ \text{There exist}B{i}^{+3}5-3=25=\text{group number.}\\ \text{This is due to inert pair effect.}\\ \text{The inert pair effect is the tendency of the}\\ \text{two electrons in the outermost atomic s-orbital}\\ \text{to remain, unshared in compounds of past}\text{transition metal.}\\ \text{So}D\text{) two is correct option .}\end{array}$