2.2. Classification of Matter http://www.ck12.org
FIGURE 2.7
This filtering apparatus uses suction to pull the water through a fine glass
filter, leaving behind a yellow-colored solid.Distillation
Distillationis a method of separating a mixture based on differences in boiling points. A distillation apparatus is
pictured in theFigure2.8.
FIGURE 2.8
A small-scale laboratory distillation ap-
paratus is used to separate substances
based on differences in their boiling
points.For example, the impure liquid could be a mixture of alcohol and water. As the mixture is heated, the alcohol begins
to boil before the water does because of its lower boiling point. The alcohol vapors rise up in the flask and into
the long cylindrical tube, which is called a condenser. Cold water is continually pumped into the outside of the
condenser, which causes the alcohol vapors to condense back into the liquid state. The purified alcohol then drips
into the flask labeled “distilled liquid,” while the water is left behind in the original flask.
Distillation is commonly used to purify water by separating it from the various dissolved minerals that are found in
natural water sources.
You can view the distillation of methanol to separate it from a dye at http://www.youtube.com/watch?v=74rOJ1GFbC0
(1:16).