The composition and formula of water

A close-up photograph of droplets of water on a bright blue surface

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Try this demonstration to determine the formula of water through the reaction of copper(II) oxide with hydrogen. Includes kit list and safety instructions.

In this experiment, students observe as a known mass of heated copper(II) oxide is reduced in a stream of hydrogen gas. The water formed by this reaction is then absorbed by sulfuric acid or anhydrous calcium chloride granules.

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