There are three phases of matter.
Solids : have definite shape and volume
Liquids: have definitely volume but take the shape of the container
Gases: take the volume and shape of the container
Substances
There are two types of substances: elements and compounds.
Elements
all of the elements can be found on the Periodic Table
Table S lists the names of all of the elements
elements can not be broken down by chemical means
Examples: Fe, Na...
Compounds
consist of atoms of two or more elements in fixed ratio
can be broken down by chemical means but not by physical
Examples: NaCl, H2O
different compounds have different chemical and physical properties
Mixtures
consist of two or more substances (elements or compounds)
can be broken down physically
can be homogeneous (uniform composition such as salt in water) or heterogeneous (nonuniform composition such as sand)
Chemical properties/changes
During a chemical change the identity of a substance changes. A chemical change represents a reaction. Chemical property refers to the reactions that the substance can do. Examples of chemical properties are: burning of wood, reaction of metal with water etc.
Physical properties/changes
Physical change does not change the identity of a substance but may change the phase or appearance of a substance. For example: melting ice, grinding chalk, etc.
Distillation:
Laboratory technique that separates two liquids based on their boiling points.
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