Question

Analysis of vitamin C shows that it contains 40.92% carbon by mass, 4.58% hydrogen and 54.50% oxygen. Determine the empirical formula of Vitamin C

Answer 1

40.92 x 1 mole C/ 12g C = 3.14 mole C

4.48 x 1mole H/ 1.008 g H = 4.43 mole H

54.50 x 1 mole O/ 16g O = 3.41 mole O

Dividing each of the three numbers by the smallest one (3.41 mol) gives a C:H:O mole ratio of 1 :1.33 :1 this gives the empirical formula: C3 x 1 H3 x 1.33 O3 x 1 or C3H4O3

Answer 2

40.92 x 1 mole C/ 12g C = 3.41 mole C

4.48 x 1mole H/ 1.008 g H = 4.43 mole H

54.50 x 1 mole O/ 16g O = 3.41 mole O

Dividing each of the three numbers by the smallest one (3.41 mol) gives a C:H:O mole ratio of 1 :1.33 :1 this gives the empirical formula: C3 x 1 H3 x 1.33 O3 x 1 or C3H4O3