https://www.khanacademy.org/science/hs-chemistry/x2613d8165d88df5e:stoichiometry-and-the-mole/x2613d8165d88df5e:mole-calculations/v/worked-example-calculating-mass-percent 2022-09-07T08:21:01.673602243Z Worked example: Calculating mass percent To calculate the mass percent of an element in a compound, we divide the mass of the element in 1 mole of the compound by the compound's molar mass and multiply the result by 100. Sal Khan video https://cdn.kastatic.org/ka_thumbnails_cache/4b68e9ce-6c0a-4c77-b5fe-a5358be51ad1_1280_720_base.png Worked example: Calculating mass percent To calculate the mass percent of an element in a compound, we divide the mass of the element in 1 mole of the compound by the compound's molar mass and multiply the result by 100. https://cdn.kastatic.org/ka-youtube-converted/enTtIDEtda8.mp4/enTtIDEtda8.mp4 338 Percentage composition https://www.khanacademy.org/science/ap-chemistry-beta/x2eef969c74e0d802:atomic-structure-and-properties/x2eef969c74e0d802:elemental-composition-of-pure-substances/e/elemental-composition-of-pure-substances 2021-04-29T07:57:01Z Elemental composition of pure substances Check your understanding of percent composition and empirical formulas in this set of free practice questions designed for AP Chemistry students. Lauren Rosebrugh exercise