Mass analysis of ascorbic acid

Question

Ascorbic acid vitamin C contains 40.92% of carbon, 4.58% hydrogen ,and 54.50% oxygen by mass. Assume a 100-g sample of ascorbic acid. How many moles of carbon, hydrogen and oxygen are present in a 100g sample of ascorbic acid?

Answer 1

Assuming 100 g of the sample, the % values then become grams.

40.92 g C x 1 mol C/12.01 g = 3.407 moles C

4.58 g H x 1 mol H/1.008g = 4.544 moles H

54.50 g O x 1 mol O/15.99 g = 3.408 moles O