Lesson 11 Notes

Substances can be classified as either pure substances or mixtures.

Solutions are mixtures.

Mixtures are two or more substances that are not chemically united and that exist in no fixed proportion to each other.

Substances are a kind of matter or material.

Matter is mass.

Solutions are homogeneous mixtures of one or more substances (the solutes) dissolved in another substance (the solvent).

Homogeneous mixtures have definite or consistent properties.

Heterogeneous mixtures are inconsistent and non-uniform in composition.

Most raw materials are mixtures of different substances. Separation techniques are used to obtain pure substances from these mixtures.

The samples you will be working with are mixtures in different phases and vary in their level of heterogeneity. None of the elements are pure substance (an element or a compound).

Samples are substances.