Question

assertion :carbon cannot form anion or cation.reason:CARBON IS tetravalent​

Answer 1

Answer: Both statement are true and second statement is correct/not correct explanation of first.

Explanation: Read it full

Now this is very controversial i must say..

See as we know a cation is anything which "donates" electron and gains positive charge. So carbon gains positive charge not by donating the electron, instead sharing it's electron density with some more electronegative group. For eg. in CCl4 has oxidation number +4 but we can't say that CCl4 is formed by 1 C⁴+ nd 4Cl- ions. It is just bonded by covalent bonds,ie, just sharing the electron densities .

Now the reason why second statement does not explain first. See it's not the tetravalency that makes it incapable of ionisation. Take Lithium or beryllium for example they rarely form anion or cation. I think the correct reason would be both tetravalency amd small size, which results in high polarizing power(now if you have no idea what it means, leave it).

So the second statement may or may not be the reason for first.