Explanation:
A molecular compound is defined as the compound in which atoms come closer to each other through sharing of electrons and results in the formation of covalent bond.
These compounds usually contain two or more number of non-metals.
Greek prefixes like mono, di, tri, tetra etc are used while naming molecular compounds as these prefixes indicate the number of atoms of each element present.
For example, is a molecular compound and its name is dichlorine heptoxide.
As di means 2, and hepta means 7.
Thus, we can conclude that for molecular compounds we use Greek, numerical prefixes in the name.