51.41%
Percentage Composition from Formulas
A more complex example is sucrose (table sugar), which is 42.11% carbon, 6.48% hydrogen, and 51.41% oxygen by mass.
Or
53.3 %
Thus the % composition of glucose by mass is carbon 40.0 % oxygen 53.3 % hydrogen 6.7 % In this way, the % composition by mass of any compound can be calculated provided that its formula is known.
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What is the percentage composition of sugar?
Element Symbol Mass Percent
Hydrogen H 6.714%
Carbon C 40.001%
Oxygen O 53.285%