how do we find out the molar mass of a chemical?

Question

(CH3CH2OH) this is what i have to find the molar mass of. i have the answer but i dont know how to do it, its 46 grams/mole

Answer 1

You just add the average masses of the elements that you have.
C --- average mass of 12 g/mole
H3 --- average mass 3 g/mol
C --- av. mass 12 g/mol
H2 --- av. mass 2 g/mol
O --- av. mass 16 g/mol
H -- av. mass 1 g/mol
When you add these up you get 46 g/mol.

I just did these in school.

I hope I helped you.

Answer 2

If you mean from a Periodic Table, you just add up the Ar values:
(2 x 12) + (6 x 1) + 16 = 46.

If you mean as an experiment, you will have to evaporate a known mass of the compound into a glass syringe at a known temperature and pressure, and measure the volume that the vapour occupies. Then use the gas laws.