Why carbon is not able to form ionic compounds?
Carbon has valency 4. To attain noble gas configuration it need to gain or lose 4 electrons so that it would form ionic compound.
1. If it gain 4 electrons it would be difficult for nucleus to hold 6 protons on to 10 electrons.
2. If it lose 4 electrons it would require lot of energy to lose 4 electrons from nucleus holding 6 protons on to just 2 electrons.
Thus carbon doesnt form ionic compounds.