Chapter 13: Physical Properties of Solutions

Question 1

solution

Answer 1

a homogeneous mixture of two or more substances; consists of a solvent and one or more solutes.

Question 2

unsaturated solution

Answer 2

one that contains less solute than the solvent has the capacity to dissolve at a specific temperature

Question 3

saturated solution

Answer 3

one that contains the maximum amount of solute that will dissolve in a solvent at a specific temperature

Question 4

Supersaturated solutions

Answer 4

contain more dissolved solute than is present in a saturated solution and are generally unstable

Question 5

Solvation occurs when

Answer 5

solute molecules are separated from one another and surrounded by solvent molecules.

Question 6

entropy

Answer 6

a measure of how dispersed or spread out its energy is.

Question 7

There is a natural tendency for the energy of a system to

Answer 7

become dispersed (entropy increases).

Question 8

Two substances with similar type and magnitude of intermolecular forces are likely to be _____ in each other

Answer 8

soluble

Question 9

Two liquids are said to be ____ if they are completely soluble in each other in all proportions.

Answer 9

miscible

Question 10

concentration

Answer 10

The amount of solute relative to the volume of a solution or to the amount of solvent in a solution

Question 11

Molality

Answer 11

the number of moles of solute dissolved in 1 kg (1000 g) solvent

Question 12

Pressure greatly influences

Answer 12

the solubility of a gas.

Question 13

Henry’s law states that

Answer 13

the solubility of a gas in a liquid is proportional to the pressure of the gas over the solution.

Question 14

Colligative properties

Answer 14

properties that depend on the number of solute particles in solution

Question 15

The colligative properties are:

Answer 15

Vapor pressure lowering.
Boiling point elevation.
Freezing point depression.
Osmotic pressure.

Question 16

Raoult’s law states that

Answer 16

the partial pressure of a solvent over a solution is given by the vapor pressure of the pure solvent times the mole fraction of the solvent in the solution.

Question 17

If both components of a solution are volatile:

Answer 17

the vapor pressure of the solution is the sum of the individual partial pressures

Question 18

ideal solution

Answer 18

obeys Raoult’s law.

Question 19

Solutions boil at a _____ temperature than the pure solvent.

Answer 19

higher

Question 20

Solutions freeze at a _____ temperature than the pure solvent.

Answer 20

lower

Question 21

Osmosis

Answer 21

the selective passage of solvent molecules through a porous membrane from a more dilute solution to a more concentrated one.

Question 22

Osmotic pressure

Answer 22

pressure required to stop osmosis

Question 23

Electrolytes undergo ______ when dissolved in water.

Answer 23

dissociation

Question 24

van’t Hoff factor

Answer 24

accounts for electrolyte dissociation

Question 25

The van’t Hoff factor (i) is ____ for all nonelectrolytes

Answer 25

1

Question 26

For strong electrolytes i should be equal to _____

Answer 26

the number of ions

Question 27

The van’t Hoff factor (i) is usually smaller than predicted due to

Answer 27

formation of ion pairs

Question 28

ion pair

Answer 28

made up of one or more cations and one or more anions held together by electrostatic forces.

Question 29

Percent dissociation

Answer 29

is the percentage of dissolved molecules (or formula units, in the case of an ionic compound) that separate into ions in a solution and this can be found using colligative properties

Question 30

Percent dissociation of a strong electrolyte is more complete at ______ concentration.

Answer 30

lower

Question 31

Percent ionization of weak electrolytes is also dependent on

Answer 31

concentration

Question 32

colloid

Answer 32

a dispersion of particles of one substance throughout another substance. (Colloid particles are much larger than the normal solute molecules.)

Question 33

colloid examples

Answer 33

``` Aerosols. Foams. Emulsions. Sols. Gels. ```

Question 34

Colloids with water as the dispersing medium can be categorized as

Answer 34

hydrophilic (water loving) or hydrophobic (water fearing).

Question 35

Hydrophobic colloids can be stabilized by the presence of

Answer 35

hydrophilic groups on their surface (think hyrdophilic head)

Question 36

Emulsification

Answer 36

the process of stabilizing a colloid that would otherwise not stay dispersed