a) Explain why carbon forms covalent bond? Carbon forming a large number of compounds – Give Two reasons. b) The formation of ammonia molecule – Explain.

a) Carbon has electronic configuration 2, 4. It could gain four electrons forming C-4 anion or lose 4 electrons to form C+4 cation. Both are not possible due to energy considerations. Carbon overcomes this problem by sharing electrons and forming covalent compounds.

Two reasons for forming large number of compounds:
1) Catenation 2) Tetra valency
b) Formation of NH3 molecule
N – 2, 5 H – 1
Three hydrogen atoms each share 1 electron with nitrogen to form three covalent bonds. And therefore, it make an ammonia molecule (NH3). Diagram: