Give a reason why carbon can neither form C4 + cations nor C4— anxious, but forms covalent compounds which are bad conductors of electricity and have low melting and boiling points.

Carbon cannot form C4 + cations nor C4- anions. The reasons are:


i. The atomic number of carbon is 6. According to electronic configuration, it has 4 electrons in its valence shell.


ii. If carbon will form C4- anions, it has to gain four electrons. In this case, the carbon will have 6 protons and 10 electrons making it difficult for the nucleus to hold them. Thus, carbon does not form C4- anions.


iii. If carbon will form a C4 + cation, it has to lose 4 electrons. A very large amount of energy will be used to remove 4 electrons from an atom. Also then the carbon will have 6 protons with just 2 electrons again making it difficult for the nucleus.


iv. Thus, instead of losing or gaining four electrons, Carbon shares it electrons forming covalent bond.


8