Chapter 8 Solution
Solution
A homogeneous mixture of two or more substances with each substance retaining its own chemical identity.
Solute – substance being dissolved.
Solvent – liquid water.
General Properties of a Solution 1. Contains 2 or more components.
2. Has variable composition.
3. Properties change as the ratio of solute to solvent is changed.
4. Dissolved solutes are present as individual particles.
5. Solutes remain uniformly distributed and will not settle out with time.
6. Solute generally can be separated from the solvent by physical means such as evaporation.
SOLUBILITY * The maximum amount of solute that will dissolve in a given amount of solvent under a given set of conditions.
* Expressed as grams of solute per 100 grams of solvent
Effect of Temperature on Solubility * Most solids become more soluble in water with increasing temperature.
* In contrast, gas solubilities in water decrease with increasing temperature.
Effect of Pressure on Solubility * Pressure has little effect on the solubility of solids and liquids in water.
* Pressure has major effect on the solubility of gases in water.
* Henry’s Law * The amount of gas that will dissolve in a liquid at a given temperature is directly proportional to the partial pressure of the gas above the liquid.
* As the pressure of a gas above the liquid increases, the solubility of the gas increases.
Saturated Solution * A solution that contains the maximum amount of solute that can be dissolved under the conditions at which the solution exists.
Supersaturated Solution * An unstable solution that temporarily contains more dissolved solute than that present in a saturated solution.
* Will produce crystals rapidly, often in a dramatic manner, if it is slightly disturbed or if it is “seeded” with a tiny crystal of solute.
Unsaturated Solution * A solution that contains less than the maximum amount of solute that can be dissolved under the conditions
A homogeneous mixture of two or more substances with each substance retaining its own chemical identity.
Solute – substance being dissolved.
Solvent – liquid water.
General Properties of a Solution 1. Contains 2 or more components.
2. Has variable composition.
3. Properties change as the ratio of solute to solvent is changed.
4. Dissolved solutes are present as individual particles.
5. Solutes remain uniformly distributed and will not settle out with time.
6. Solute generally can be separated from the solvent by physical means such as evaporation.
SOLUBILITY * The maximum amount of solute that will dissolve in a given amount of solvent under a given set of conditions.
* Expressed as grams of solute per 100 grams of solvent
Effect of Temperature on Solubility * Most solids become more soluble in water with increasing temperature.
* In contrast, gas solubilities in water decrease with increasing temperature.
Effect of Pressure on Solubility * Pressure has little effect on the solubility of solids and liquids in water.
* Pressure has major effect on the solubility of gases in water.
* Henry’s Law * The amount of gas that will dissolve in a liquid at a given temperature is directly proportional to the partial pressure of the gas above the liquid.
* As the pressure of a gas above the liquid increases, the solubility of the gas increases.
Saturated Solution * A solution that contains the maximum amount of solute that can be dissolved under the conditions at which the solution exists.
Supersaturated Solution * An unstable solution that temporarily contains more dissolved solute than that present in a saturated solution.
* Will produce crystals rapidly, often in a dramatic manner, if it is slightly disturbed or if it is “seeded” with a tiny crystal of solute.
Unsaturated Solution * A solution that contains less than the maximum amount of solute that can be dissolved under the conditions