Question

How is the mass of a compound related to its chemical formula?.....I needed some explanations and examples. thanks

Answer 1

Mass is a physical quantity which represents the amonut of matter present in a paticular substance.

So mass of a compound depends on its constituents.

For example take water water :

It's chemical formula is H2O. The mass of depends on the mass of both hydrogen and oxygen.

1 mole of hydrogen molecules weigh---------------- 2g

1mole of oxygen molecules weigh------------------ 16g

hence the mass of 1 mole of water molecules is-------- (2+16)g = 18g

example 2: Take CO2 :

carbon dioxide is made up of 1mole of carbon atoms and 1mole of oxygen molecules.

Hence the molecular mass of CO2 = mass of carbon+ mass of oxygen

Mass of 1 mole of carbon is--------------12g

Mass of 1 mole of oxygen molecules-----32g

Hence the mass of CO2 = (12+ 32)g

                                    =44g

Hence the mass of a chemical compound depends on its costituents mass.