Translations:Adventist Youth Honors Answer Book/Health and Science/Chemistry/78/en
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As the steel wool rusts, it uses up oxygen trapped in the glass. This reduces the volume of air inside the glass, and the atmospheric pressure outside the glass will compensate by pushing down on the water inside the bowl. This will in turn push the water in the glass higher. Verify by comparing the current water level to the level marked at the beginning of the experiment.
