Keep in mind that, one particle of a compound will dependably contain entire quantities of molecules of every constituent component.
Thus, if you somehow happened to pick a 100-g test of serine, you would wind up with the accompanying information:
34.95 g → carbon
6.844 g → hydrogen
46.56 g → oxygen
13.59 g → nitrogen
Utilize the molar mass of every component to decide how may moles of every you get in one mole of serine:
For C: 34.95g x 1 mole C/12.011 g = 2.91 moles C ≈ 3 moles C
For H: 6.844 g x 1 mole H/1.00794 g = 6.80 moles H ≈ 7 moles H
For O: 46.56 g x 1 mole O/15.9994 g = 2.91 moles O ≈ 3 moles O
For N: 13.59 g x 1 mole N/14.00674 g = 0.97 moles N ≈ 1 mole N
Since you're still in the roughly equivalent to 100 g mol^−1, you can round these qualities to the closest whole number.
Hence, on the off chance that one mole of serine contains that numerous moles of every component, you can state that its molecular formula is
C3H7N1O3 ⇒ C3H7NO3 would be the molecular formula
Since 3:7:1:3 is additionally the littlest entire number proportion that can exist between these qualities, this will likewise be serine's empirical formula.
C3H7NO3 would be the empirical formula.