Question

State the reasons, why carbon cannot

1. Lose four electrons to form C⁴⁺ cation and
2. Gain four electrons to form C^4- anion.

How does carbon overcome this problem to form compounds?

Answer 1

Elements forming ionic compounds achieve this by either gaining or losing electrons from the outermost shell. In the case of carbon, it has four electrons in its outermost shell and needs to gain or lose four electrons to attain a noble gas configuration. If it were to gain or lose electrons -

1. It could lose four electrons forming C⁴⁺ cation. But it would require a large amount of energy to remove four electrons leaving behind a carbon cation with six protons in its nucleus holding on to just two electrons.
2. It could gain four electrons forming C^4- anion. But it would be difficult for the nucleus with six protons to hold on to ten electrons, that is, four extra electrons.

Carbon overcomes this problem by sharing its valence electrons with other atoms of carbon or with atoms of other elements.