Topic: Percentage Composition Sugar C12H22O11 is made up of 42.1 % carbon, 6.4 % Hydrogen and 51.5% oxygen. Draw a pie- graph representation of this

Percent Part X 100% Whole Percent Composition by mass = Mass of element X 100 Mass of compound

Percent Compositions can help us identify unknown pure substance

Percent Composition of H2O % H = 2g x 100 = 11.1% 18g % O = 16.0g x 100 =88.9% 18.0g 100.0% H = 2x 1 = 2g O = 1 x 16=16g 18g

Percent Composition of C6H12O6 C = 6 x 12 = 72g H = 12 x 1 = 12g O = 6 x 16 = 96g ______ 180g /180 x 100 = 40.0% /180 x 100 = 6.7% 53.3% /180 x 100 =

Please NOTE: Sum of individual element %’s must add up to almost 100% usually works out exact if round to 2 decimal places