Final answer:
The property used to differentiate between pure substances and mixtures is composition.
Step-by-step explanation:
The property used to differentiate between pure substances and mixtures is composition.
A pure substance is composed of only one type of atom or molecule and has a fixed composition. A mixture, on the other hand, is a combination of two or more pure substances and can have varying compositions.
For example, if we have a sample of water (H2O), it is a pure substance because it consists of only water molecules. However, if we have a mixture of water and salt (NaCl), the composition is not fixed, as we can have different ratios of water to salt.
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