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Percent Composition

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What is Percent Composition?

Percent composition is the percentage by mass of each element in a compound. It is calculated as: % element = (mass of element in 1 mol / molar mass of compound) × 100%. Percent composition is used to derive the empirical formula of a compound from elemental analysis data. For example, water is approximately 11.19% hydrogen and 88.81% oxygen by mass.

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Term Percent Composition

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Percent composition is the percentage by mass of each element in a compound. It is calculated as: % element = (mass of element in 1 mol / molar mass of compound) × 100%. Percent composition is used to derive the empirical formula of a compound from elemental analysis data. For example, water is approximately 11.19% hydrogen and 88.81% oxygen by mass.

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