Question
When an iron object rusts, its mass increases. When a match burns, its mass decreases. Do these observations violate the law of conservation of mass? Explain.
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This means that the total mass of the reactants in a chemical reaction must equal the total mass of the products. Show more…
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Many reactions seem to violate the law of conservation of mass. For example, (a) when an iron object rusts, the rusty object has a greater mass than before, and (b) when a piece of charcoal burns, the remaining material (ash) has less mass than the charcoal. Explain these observations, and suggest an experiment that would demonstrate that mass is conserved in each case.
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