How does knowing a molecular formula allow you to calculate molecular weight?

Answer 1

Yes it does.

Ex.: C6H12O6 is glucose, or sugar. To find the Atomic Mass, you must add up all the masses of each element like so:

C=12.01 mol.g

H= 1.01 mol.g

O= 16.00 mol.g

(12.01 x 6) + (1.01 x 12) + (16.00 x 6) = 180.18 mol.g is glucose's atomic mass. This can be done with any compound if you have the empirical formula, and the weights for the elements found on the Periodic Table.