Guide Questio 1. What is a pure substance?
2. What are the properties of pure substances?
3. Tabulate your answers about pure substances.
Pure Substances
Set of
Properties
Appearance
Melting point
Boiling point

Pure substance refers to a substance that has a fixed chemical composition. For example, water, air, and nitrogen. Properties of pure substance are the following:

So we can conclude that pure substance has fixed chemical composition throughout its body.

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1. A pure substance is defined as a substance that is consists of only one chemical and free from any contamination. For example: honey.

2. Properties of pure substance: homogeneous in nature, fixed boiling and melting points, and uniform composition.

3. Appearance -  constant or uniform

Melting Point - Fixed throughout the sample

Boiling Point - Fixed throughout the sample

the old alchemists made significant contributions to science even though there starting premises were off a bit. their conclusions after failure would steer them into better directions for investigation. science is no more than close observation and the initial mistakes result in rethinking and retrying experiments.