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In support of all the students who are displaced from school due to the Corona virus. Access to physics zone and chemistry zone lessons are now available free of charge. This will be maintained at least through August 1st 2020. Learn and be well.

Chemistry Lessons Review Links

Classifications of Matter

The flowchart below is a quick way to see the relationship between the various classifications or types of matter.  This does not represent states (solid, liquid, gas, plasma) of matter.  By answering the questions as you run into them going down the chart you will determine what classification or category a particular sample of matter falls into.

A substance that can not be broken down into simpler substances.  (Note: protons, neutrons, and electrons are not considered substances.)  For any single element, all atoms have the same number of protons.  There may be a different number of neutrons but they are considered isotopes of the same element. Therefore, it is the number of protons that separates one element from another.
Compound (molecule)
Any substance that is formed by a combination of elements in fixed proportions.  This means a molecular formula can be written for them (ie. H2O, CO2).  The formation of a compound requires a chemical reaction.  Compounds can not be separated by physical means (hammers, pry bars, chisels, magnets, distillation, crystallization, or filters will not separate them).
A homogeneous mixture of a liquid, called the solvent, and another compound, called the solute. In a solution, the molecules of the solute are completely surrounded by solvent. There is usually some physical interaction between the molecules of solvent and the molecules of solute. Can be separated by physical means.
Homogeneous Mixture (same category as a Solution)
A system of two or more substances (elements or compounds) that are interspersed like the gases making up the air. Can be separated by physical means. The substances have distinct chemical properties.
Heterogeneous Mixture
A system of two or more substances (elements or compounds) that have distinct chemical and physical properties. Examples could include mixtures of salt and sand, oil and water, crackerjacks, and dirt.