Covalent compounds are named using a set of rules that involve the following:

1. Prefixes:

* Mono- (1)

* Di- (2)

* Tri- (3)

* Tetra- (4)

* Penta- (5)

* Hexa- (6)

* Hepta- (7)

* Octa- (8)

* Nona- (9)

* Deca- (10)

2. Nonmetal Names:

* The element furthest to the right on the periodic table is named last, and its name is unchanged.

* The element to the left on the periodic table is named first, and its name has a prefix indicating the number of atoms present in the molecule.

3. Exceptions:

* If the first element has only one atom, the prefix "mono-" is usually omitted.

* For elements in group 17 (halogens), the ending "-ine" is changed to "-ide".

* Some compounds have common names that are used instead of their systematic names (e.g., water (H₂O), ammonia (NH₃)).

Examples:

* CO: Carbon monoxide (one carbon, one oxygen)

* CO₂: Carbon dioxide (one carbon, two oxygens)

* SO₂: Sulfur dioxide (one sulfur, two oxygens)

* SO₃: Sulfur trioxide (one sulfur, three oxygens)

* P₂O₅: Diphosphorus pentoxide (two phosphorus, five oxygens)

* N₂O₄: Dinitrogen tetroxide (two nitrogen, four oxygens)

* HCl: Hydrogen chloride (one hydrogen, one chlorine)

* H₂S: Dihydrogen sulfide (two hydrogen, one sulfur)

Remember:

* Covalent compounds are typically formed between two nonmetals.

* The prefixes are used to indicate the number of each type of atom in the molecule.

* The names of covalent compounds are usually lowercase.

Let me know if you have any specific covalent compounds you'd like to name!