Question

Give reasons for (1)[sif62]- is known whereas [sicl6]-2 is not known. (2) diamond is a covalent solid, yet it has highest melting point. (3) boric acid is considered a weak base. (4) bf3 behaves as levis acid. (5) co2 is a gas while sio2 is a solid at room temperature

Answer 1

1) Si can hold 6 flourine atoms due to their small size, but Cl has larger size.

2) Diamond has high melting point due to its complex structure.

3) Boric acid has three B-OH bonds, which makes it a base.

4) BF3 has incomplete octet (only 6 electrons with Boron)

5) Molecular mass increases, and so the melting point.