Answer:
One of the most notable characteristics of a mixture is that it does not have a fixed composition. Water, a compound, always has 11.2 percent hydrogen and 88.8 percent oxygen by weight. Brass is a mixture because it has varying amounts of copper and zinc. One type of brass may contain as much as 45 percent zinc, while another type may contain around 10 percent zinc. Mixtures may also have changing properties depending on their composition. The boiling point of a mixture of alcohol and water varies based on how much alcohol is in the mixture.
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