Express the composition of each of the following compounds as the mass percents of its elements...?

Question

59) Express the composition of each of the following compounds as the mass percents of its elements.

a) formaldehyde, CH2O
b) glucose, C6H12O6
c) acetic acid, HC2H3O2

Answer 1

Example: b) glucose.
a. determine the molecular mass of the compound: 6*12+12*1+6*16= 180
Percent of C= 6*12/180 x 100
percent of H= 12*1/180 x 100
percent of O= 6*16/180 x 100
and of course, the percents should add to 100.

Answer 2

Acetic acid, HC2 H3 O2