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Solving Problems: A Chemistry Handbook
Chemistry: Matter and Change
139
Mixtures and Solutions
Mixtures and Solutions
SOLVING PROBLEMS:
A CHEMISTRY HANDBOOK
CHAPTER
14
14.1 What are solutions?
Solutions are homogeneous mixtures that contain a solute and a solvent. Solutions, solutes, and solvents may be solid, liquid, or
gaseous. A substance that dissolves in a solvent is said to be soluble
in that solvent. A substance that does not dissolve in a solvent is said
to be insoluble in that solvent. Two liquids that are soluble in each
other are said to be miscible. Liquids that are not soluble in each
other are immiscible.
A soluble substance is able to dissolve in a solvent because
attractive forces between solvent and solute particles are strong
enough to overcome the attractive forces holding the solute particles
together. Solvent particles surround solute particles to form a solution in a process called solvation. Solvation in water is also called
hydration.
In general, “like dissolves like”; that is, polar substances tend to
be soluble in polar solvents, and nonpolar substances tend to be soluble in nonpolar solvents. When an ionic compound dissolves in
water, a polar solvent, the attractions between the water dipoles and
the ions cause the ions to become solvated. The ions break away
from the surface of the ionic solid and move into solution. The overall energy change that occurs during solution formation is called the
heat of solution.
There are three common ways to increase the collisions between
solute and solvent particles and thus increase the rate at which the
solute dissolves: agitating the mixture, increasing the surface area of
the solute, and increasing the temperature of the solvent. Increasing
the temperature causes collisions to become more frequent and to
have greater energy.
The solubility of a solute is the maximum amount of the solute
that will dissolve in a given amount of solvent at a specified temperature and pressure. Solubility is usually expressed in grams of
solute per 100 g of solvent. A solution that contains the maximum
amount of dissolved solute for a given amount of solvent at a specific temperature and pressure is called a saturated solution. An
Solving Problems: A Chemistry Handbook
Chemistry: Matter and Change
139
Mixtures and Solutions
Mixtures and Solutions
SOLVING PROBLEMS:
A CHEMISTRY HANDBOOK
CHAPTER
14
14.1 What are solutions?
Solutions are homogeneous mixtures that contain a solute and a solvent. Solutions, solutes, and solvents may be solid, liquid, or
gaseous. A substance that dissolves in a solvent is said to be soluble
in that solvent. A substance that does not dissolve in a solvent is said
to be insoluble in that solvent. Two liquids that are soluble in each
other are said to be miscible. Liquids that are not soluble in each
other are immiscible.
A soluble substance is able to dissolve in a solvent because
attractive forces between solvent and solute particles are strong
enough to overcome the attractive forces holding the solute particles
together. Solvent particles surround solute particles to form a solution in a process called solvation. Solvation in water is also called
hydration.
In general, “like dissolves like”; that is, polar substances tend to
be soluble in polar solvents, and nonpolar substances tend to be soluble in nonpolar solvents. When an ionic compound dissolves in
water, a polar solvent, the attractions between the water dipoles and
the ions cause the ions to become solvated. The ions break away
from the surface of the ionic solid and move into solution. The overall energy change that occurs during solution formation is called the
heat of solution.
There are three common ways to increase the collisions between
solute and solvent particles and thus increase the rate at which the
solute dissolves: agitating the mixture, increasing the surface area of
the solute, and increasing the temperature of the solvent. Increasing
the temperature causes collisions to become more frequent and to
have greater energy.
The solubility of a solute is the maximum amount of the solute
that will dissolve in a given amount of solvent at a specified temperature and pressure. Solubility is usually expressed in grams of
solute per 100 g of solvent. A solution that contains the maximum
amount of dissolved solute for a given amount of solvent at a specific temperature and pressure is called a saturated solution. An