Amolecule with a single covalent bond is co cl2 co2 n2

Cl2

Explanation:

Chemical bonds in general can be classified as ionic and covalent

Ionic bonds are formed by the complete transfer of electrons from one atom to the other while covalent bonds are formed by the mutual sharing of electrons.

1) In CO i.e. carbon monoxide the C and O atoms are connected by 3 covalent bonds

2) In Cl2, the Cl atoms are connected by 1 covalent bond

3) IN CO2, the central C atom is bonded to O atoms by 2 covalent bonds

4) In N2, the N atoms are connected by 3 covalent bonds.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.

catya that's not even a b or c