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Topic 1.3 · Elemental Composition of Pure Substances

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AP Chemistry · Topic 1.3: Elemental Composition of Pure SubstancesOpen topic

Practice question

Original PrepAtlas question. This is not an official College Board question.

A pure compound is40.0% C,6.7% H,and53.3% O by mass. Use atomic masses C12.0,H1.0,O16.0. Which empirical formula best matches the rounded data?
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