Which pair of molecules are both compounds?
a. h2, co2
b. h20, n2
c. co2, h20
d. o2, c6h1206

The correct option is C. CO2, H20 are both compounds.

Explanation:

Compounds can be described as substances which are produced when atoms of different elements join together through the formation of chemical bonds.

In the option C, both CO2 and H2O are formed by the atoms of different elements. Carbon and two molecules of oxygen join to form carbon dioxide. Hydrogen and two molecules of oxygen join to form H2O. Hence, the correct option is C.

Option A is false because H2 is a substance made up of atoms of same element i.e Hydrogen. Option B is false because N2 is a molecule made up of the same atoms of nitrogen. Option C is false because O2 is made up of the same oxygen atoms.