What Are Some Examples of Covalent Compounds?

Common Covalent Compounds

Covalent compound
Ethyl alcohol or ethanol is an example of a molecular compound containing atoms joined by covalent bonds. Science Photo Library - PASIEKA/Getty Images

These are examples of covalent bonds and covalent compounds. Covalent compounds also are known as molecular compounds. Organic compounds, such as carbohydrates, lipids, proteins, and nucleic acids, are all examples of molecular compounds. You can recognize these compounds because they consist of nonmetals bonded to each other.

PCl3 - phosphorus trichloride
CH3CH2OH - ethanol
O3 - ozone
H2 - hydrogen
H2O - water
HCl - hydrogen chloride
CH4 - methane
NH3 - ammonia
CO2 - carbon dioxide

So, for example, you would not expect to find covalent bonds in a metal or alloy, such as silver, steel, or brass. You would find ionic rather than covalent bonds in a salt, such as sodium chloride.

What Determines Whether a Covalent Bond Forms?

Covalent bonds form when two nonmetallic atoms have the same or similar electronegativity values. So, if two identical nonmetals (e.g., two hydrogen atoms) bond together, they will form a pure covalent bond. When two dissimilar nonmetals form bonds (e.g., hydrogen and oxygen), they will form a covalent bond, but the electrons will spend more time closer to one type of atom than the other, producing a polar covalent bond.