III. Read the following text. What is the meaning of the words and word-combinations
in bold?
TEXT B
COLLOIDS
A
colloid is one of the three primary types of mixtures, with the other two being a
solution and
suspension. A colloid is a solution that has
particles ranging between 1 and
1000 nanometers in diameter, yet are still able to remain evenly distributed throughout the
solution. These are also known as colloidal
dispersions because the substances remain
dispersed and do not
settle to the bottom of the container. In colloids, one substance is evenly
dispersed in another. The substance being dispersed is referred to as being in the dispersed
phase, while the substance in which it is dispersed is in the continuous phase.
Properties of colloids. In order to be classified as a colloid, the substance in the
dispersed phase must be larger than the size of a molecule but smaller than what can be seen
with the
naked eye. This can be more precisely quantified as one or more of the substance's
dimensions must be between 1 and 1000 nanometers. If the dimensions are smaller than this
the substance is considered a solution and if they are larger than the substance is a suspension.
Classifying colloids. A common method of classifying colloids is based on the phase
of the dispersed substance and what phase it is dispersed in. The types of colloids includes
sol, emulsion, foam, and aerosol.
1.
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