Final answer:
A phase change involves a transition between states of matter, while a mixture is a physical combination of different substances. A chemical reaction involves the rearrangement of atoms or molecules to form new substances.
Step-by-step explanation:
At the atomic level, a phase change refers to a transition between different states of matter, such as the conversion of water from a liquid to a solid when freezing occurs. The arrangement and motion of atoms or molecules change, but their identities remain the same.
A mixture is a combination of different substances that are physically mixed together, but each retains its own chemical identity. Atoms or molecules in a mixture interact with each other, but do not undergo any chemical changes.
In a chemical reaction, there is a rearrangement of atoms or molecules to form new substances. Bonds are broken and formed, resulting in the creation of different chemical species with changed properties.
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