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DemonstrationsIntro › 1.2

Lecture Demonstrations

Introduction to Chemistry, Matter, The Elements

1.2 Definitions of Matter I (Copper vs Copper sulfate)

Subjects: Introduction to chemistry, definitions of matter

Description: This demo illustrates two concepts: the difference between an element and a chemical compound as well as the difference between heterogeneous and homogeneous mixtures (solutions).


  • Copper metal
  • Copper Sulfate - CuSO4
  • 400 ml beaker
  • Water
  • Stir plate*
  • Stir bar
  • Spatula

*Shared item. Located in the top drawer opposite the chemical storage cabinets or on the shelf above the center bench.


  1. Prior to the demo, use the copper metal and CuSO4 to illustrate the concept of an element versus a chemical compound, both of which are pure substances.
  2. Place a beaker filled with water on a stir plate with a stir bar.
  3. Use a spatula to scoop in chunks of CuSO4.
  4. The copper sulfate will dissolve to produce a blue homogeneous solution.

Discussion: This demo illustrates the following concepts:

  • An element is a substance composed of one type of atom.
  • A chemical compound is a pure substance composed of two or more different elements held together by chemical bonds.
  • Homogeneous means a mixture that consists of two or more substances in the same phase (ex: solution).
  • Heterogeneous means a mixture in which the uneven texture of a material can be detected.

Disposal: Dispose of copper sulfate solution in appropriate aqueous waste container.

1. J. Kotz, P. Treichel, J. Townsend; Chemistry and Chemical Reactivity, 7th Ed; Thomson Brooks/Cole; 2009

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