A student records the mass of a piece of iron. The iron is then left outside until it rusts.
What type of reaction occurs, and how does the mass of the object after rusting compare with its original mass?
synthesis; the mass of the rusted iron is greater
decomposition; the mass of the rusted iron is greater
decomposition; the mass of the rusted iron is less
synthesis; the mass of the rusted iron is les
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Decomposition; the mass of the rusted iron is greater
When iron rusts, it undergoes a chemical reaction with oxygen in the air to form iron oxide. This is a type of decomposition reaction, as the iron is breaking down into a new substance. The mass of the rusted iron is greater than the original iron, as the iron oxide has a larger mass than the original iron.