Chemical Bonding — Important Questions

Carbon, Hydrogen, Oxygen, Nitrogen

Carbon, hydrogen, oxygen, and nitrogen are non-metals that can form covalent bonds by sharing electrons and can also participate in ionic bonding under certain conditions. Helium is a noble gas and rarely forms bonds.

High melting points, Conduct electricity when dissolved in water, Usually soluble in polar solvents, Form crystalline solids

Ionic compounds have high melting and boiling points due to strong electrostatic forces, conduct electricity in solution due to mobile ions, are soluble in polar solvents, and form regular crystalline structures.

Complete valence shell

Noble gases have complete valence shells (8 electrons except helium which has 2), making them stable and unreactive under normal conditions.

Pyramidal

NH₃ has a pyramidal shape due to the presence of one lone pair of electrons on nitrogen, which causes bond angle deviation from tetrahedral geometry.