Binary molecular compounds are composed of two elements

Non-metal

Explanation:

Molecular compounds are formed through covalent bonds. Covalent bonds occur between non-metals only and they form what we call molecules, hence the name molecular compound.

An example of a molecular compound is carbon monoxide or CO. Carbon is a non-metal and oxygen is a non-metal, so you know that they form a covalent bond.

That's the difference with ionic compounds. Ionic bonds form ionic bonds and these bonds occur between a metal and a non-metal.

u i forgot the answer?

that's what i got you can count the number of atoms