Question

The stability of dihalides of Si, Ge, Sn and Pb increases steadily in the sequence:
A. \[Pb{X_2} < Sn{X_2} < Ge{X_2} < Si{X_2}\]
B. \[Ge{X_2} < Si{X_2} < Sn{X_2} < Pb{X_2}\]
C. \[Si{X_2} < Ge{X_2} < Pb{X_2} < Sn{X_2}\]
D. \[Si{X_2} < Ge{X_2} < Sn{X_2} < Pb{X_2}\]

Answer 1

Hint: The modern periodic table has a total of 118 elements. The horizontal rows are called groups and vertical columns are called groups. The modern periodic table has eighteen groups and seven periods.

Complete step by step answer:
Group-14 elements are Carbon (C), Silicon (Si), Germanium (Ge), Tin (Sn) and Lead (Pb). The general outermost electronic configurations for group-14 elements is \[n{s^2}n{p^2}\].
Size of the atom/ion increases as we move down the group in the periodic table and it decreases from left to right across the periodic table. Inert pair effect occurs most commonly in group 13-17. Inert pair effect is nothing but the tendency to make \[n{s^2}\] pair of electrons as inert ie) it is not involved in bonding. The reason for non-bonding of s-subshell is when s-orbital is tightly held by nucleus which is due to poor shielding of p-subshell, then the inert nature of s-subshell becomes predominant and thus, it is not involved in bonding. As a result, the oxidation state of elements will be affected by the inert pair effect. The best example is \[P{b^{2 + }}\] more stable than \[P{b^{4 + }}\] due to inert pair effects. Generally, the inert pair effect increases down the group due to its atomic size.
In group-14 , all elements except carbon show inert pair effect. The stability of dihalides of Si, Ge, Sn and Pb increases steadily in the sequence of \[Si{X_2} < Ge{X_2} < Sn{X_2} < Pb{X_2}\]

So, the correct answer is Option D.

Note: Group-14 comes under p-block elements in the periodic table. p-block elements have their valence electrons in the p-subshell. Generally, the non-metallic character increases from left to right across the periodic table. The reactivity of the elements increases from left to right across the periodic table and it decreases down the group.