Question

Which is correct order for group $-14$ elements?

• A. $C{X}_2<Si{X}_2<Ge{X}_2<Sn{X}_2:$ Order of stability
• B. $C{O}_2>Si{O}_2>Ge{O}_2:$ Order of acidic character
• C. $C>Si>Ge\simeq Sn>Pb:$ Tendency for catenation
• D. $C>Si>Ge>Sn>Pb:$ Order of $\text{I.E.}$

Answer 1

Answer: (A), (B), (C)

$C>Si>Ge\simeq Sn>Pb:$ Tendency for catenation

(A) Dut to inert pair effect, the stability of $+2$ oxidation state as we move down the group increases.
(B) As we move down the group, electronegativity decreases. Hence, acidic order decreases.
(C) Down the group the size increases and electronegativity decreases, and, thereby, tendency to show catenation decreases.
(D) Correct order of $\text{I.E. : C > Si > Ge > Sn < Pb}$
As we move down the group, the $\text{I.E.}$ decreases, due to increase in atomic size, thereby, increasing the distance of e from nucleus. The first $\text{I.E.}$ of $\text{Pb}$ is slightly higher than $\text{Sn}$ due to lanthanide contractions.