Mixtures and Solutions
Most of the objects around us are not pure substances. Instead, they are
mixtures. A mixture is a combination of two or more different kinds of matter, each of
which keeps its own physical properties.
In some mixtures it’s easy to tell that each type of
matter keeps its physical properties, because you can still
see the parts of the mixture. If sugar and iron filings are
mixed together, for example, you can still see the individual
sugar grains and the iron filings.
Mixtures can be separated into the substances that make them up. The method
used to separate a mixture depends on the physical properties of the substances in the
mixture. In a mixture of iron filings and sugar, the iron filings keep their physical
property of magnetism. Since sugar doesn’t have this property, you can separate the
mixture with a magnet.
Sand is a mixture of solids. You can still see the different types of
solids after they are mixed together.
Sea water is a mixture of salts and water. The salts in sea water
can be separated from the water by evaporation.
If sugar is mixed with water, it’s not easy to tell what is in the mixture. The sugar
seems to disappear. But if you taste the mixture, you will find that the water is sweet.
The sugar has kept its physical property of taste. In a mixture
of sugar and water, the sugar dissolves in the water. When
one substance dissolves in another, the two form a solution.
A solution is a type of mixture in which particles of the two
substances are evenly mixed. Solutions cannot be easily
separated.
√What is the difference between a mixture and a
solution?