Vitamin c,which may or may not be affective in preventing cold,is an organic compound containing carbon,hydrogen and oxygen.analysis of a carefully purified sample give c=40.9%,h=4.58%,o=5.45%.from another experiement to be 180.from these data,determine:(a)the empirical formula of vitamin c.(b)the molecula formula.

You didn't type in part of the question; i.e., you meant to say that the molar mass was 180. Also, note that the perentages DO NOT add up to 100% and they must. Perhaps that 5.45% O really is 54.5

Take a 100 g sample which gives you 40.9 g C, 4.58 g H, 54.5 g O.
Convert to mols.
mols C = 40.9/12 = about 3.4
mols H = 4.58/1 = about 4.6
mols O = 54.5/16 = 3.4
Now to find the empirical formula. Divide all by the smallest; i.e.,
mols C - 3.4/3.4 = 1
mols H = 4.6/3.4 = 1.35
mols O = 3.4/3.4 = 1.
So the empirical formula, in whole numbers, is C3H4O3 and the empirical mass is 88,
molar mass i= (empirical mass x whole number)
180 = 88*whole number. You solve for the whole number
Post your work if you need further assistance.