Explain the following : (i) CO 2 is a gas whereas SiO 2 is solid. (ii) Silicon forms SiF 6 2- ion whereas the corresponding fluoro compound of carbon is not known.

Question

Philoid · Accepted Answer

(i) Carbon has a much smaller size compared to silicon.

Due to its small size it forms strong double bonds with oxygen atom (due to ) to give discrete CO₂ molecules.

Silicon atom has a large size and does not form good with other atoms. It forms four single covalent bonds with oxygen atoms. Each oxygen atom is linked with two Si atoms. Thus, a large giant molecule of 3-d structure comes into existence.

Thus, CO₂ is a gas whereas SiO₂ is solid.

(ii); Silicon has lower energy 3-d orbital so it can expand its octet givingsp³d² hybridization while d-orbitals are not present in the valence shell of carbon. It can undergo sp³-hybridisation only. The size of carbon atom is very small to accommodate six F^- anions

Thus, carbon is unable to form CF^6- anion.

Explain the following :(i) CO2 is a gas whereas SiO2 is solid.(ii) Silicon forms SiF62- ion whereas the corresponding fluoro compound of carbon is not known.

Explain the following :
(i) CO₂ is a gas whereas SiO₂ is solid.

(ii) Silicon forms SiF₆^2- ion whereas the corresponding fluoro compound of carbon is not known.