36 Chapter 2 • Solutions NEL
2.1 Solutes and Solvents
Have you ever made iced tea by mixing a powder and water (Figure 1)?
If so, did you use more powder or more water to make the drink?
Yo u p r o b a b l y m i x e d a l o t o f w a t e r w i t h a s m a l l a m o u n t o f p o w d e r .
What kind of mixture is iced tea? It looks like a pure substance, but
you know that it contains at least two components (water and tea). It
is a homogeneous mixture, or solution. Th e powder mixes evenly, or
dissolves, into the water to make the solution.
Most solutions are made by dissolving a small quantity of one type
of matter into a much larger quantity of another type of matter. Th e
part that is present in the larger quantity is called the solvent. Th e part
that is present in the smaller quantity is called the solute. Th e solutes
are the parts of the solution that dissolve. Solutions are generally made
by dissolving one or more solutes in a solvent.
Liquid Solutions
Yo u a r e p r o b a b l y m o s t f a m i l i a r w i t h s o l u t i o n s t h a t a r e l i q u i d s . Th ese
all have liquid solvents. In food preparation, the solvents are usually
liquids like water or vegetable oil. In iced tea, water is the solvent.
Wat e r is t h e m o s t c o m mo n s ol v e nt o n E a r th .
Other solvents, besides water, are also useful. Ethanol is the solvent
in perfume. Turpentine is a solvent that is used with paints. Ethyl
acetate is one of the solvents in nail polish (Figure 2).
Th e solutes that dissolve in liquids may be solids, liquids, or gases.
Salt and sugar are common solid solutes. Acetic acid is a liquid solute
that can be added to water to form vinegar. Gases such as carbon
dioxide and nitrogen dissolve in our blood and are carried around our
bodies. Can you think of other solids, liquids, and gases (solutes) that
dissolve in liquids to form solutions?
dissolve: to mix one type of matter
into another type of matter to form
a solution
solvent: the larger part of a solution;
the part of a solution into which the
solutes dissolve
solute: the smaller part of a solution;
the part of a solution that dissolves in
the solvent
Figure 1 This iced tea was made by
dissolving iced tea powder in water.
Figure 2 Ethanol, turpentine, and ethyl acetate are useful solvents for matter that does not
dissolve in water.
During Reading:
Comparisons
Comparisons are used to make
clear what is the same and
what is different about two or
more items. As you read this
section, compare characteristics
of solvents and solutes. How
are they similar? How are they
different? How does making
comparisons help you to
better understand solvents and
solutes?
LINKING TO LITERACY
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