Question

Which of the following is/are correct for group 14 elements?

• A. The (general) tendency for catenation decreases down the group
• B. They all form oxides of the form $E{O}_2$
• C. The ability of an element to form p$\pi -$p$\pi$ bond with itself increases down the group
• D. The stability of the di-haldies is in the order $C{X}_2<Si{X}_2<Ge{X}_2<Sn{X}_2<Pb{X}_2$

Answer 1

Answer: (A), (B), (D)

The stability of the di-haldies is in the order $C{X}_2<Si{X}_2<Ge{X}_2<Sn{X}_2<Pb{X}_2$

Catenation is the highest for $C$ followed by (Si\) and then it decreases as we go down the group (in general). Like $C{O}_2$ and $Si{O}_2$, all the elements form oxides of the form $E{O}_2$. As we go down the group, the ability of an element to form p$\pi -$p$\pi$ bond with itself decreases. This can be explained by the progressively weaker non-axial overlap of the $np$ orbitals. Due to the inert pair effect, +2 oxidation state progressively becomes more stable as we go down the group (general trend). Hence, the stability of the dihalides is of the order: $C{X}_2<Si{X}_2<Ge{X}_2<Sn{X}_2<Pb{X}_2$.