Chapter 12 Flashcards

1
Q

solution

A

A solution is composed of two parts: the solute and the solvent.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

solute

A

The gas (or solid) in a solution of gases (or solids), or the component present in the smaller amount.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

solvent

A

The liquid in the case of a solution of gases or solids, or the component present in the larger amount.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

miscible

A

Fluids that mix with or dissolve in each other in all proportions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

immiscible

A

Fluids that do not dissolve in each other

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

saturated solution

A

is in equilibrium with respect to the amount of dissolved solute.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

The rate at which the solute leaves the solid state equals

A

the rate at which the solute returns to the solid state.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

solubility

A

the amount that dissolves in a given quantity of solvent at a given temperature.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

unsaturated solution

A

is a solution not in equilibrium with respect to a given dissolved substance and in which more of the substance can be dissolved.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

supersaturated solution

A

a solution that contains more dissolved substance than a saturated solution does.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

when does a supersaturates solution occuer

A

when a solution is prepared at a higher temperature and is then slowly cooled. This is a very unstable situation, so any disturbance causes precipitation.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Solubility can be understood in terms of two factors:

A
  1. The natural tendency toward disorder favors dissolving

2. The relative forces between and within species must be considered.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Stronger forces within solute species _________ dissolving

A

oppose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Stronger forces between species _____ dissolving.

A

favor

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

“Like dissolves like.”

A

solutes dissolve in solvents that have the same type of intermolecular forces.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

The stronger ion-dipole force between the ion and the solvent—that is, hydration energy—________ dissolving.

A

favors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

A stronger force between ions—that is, lattice energy—_______ dissolving.

A

opposes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

The process of dissolving occurs at the

A

surfaces of the solid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

12 | 14In most cases, solubility increases with increasing temperature. However, for a number of compounds, solubility decreases with increasing temperature. Why?

A

The difference is explained by differences in the heat of solution.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

When dissolving absorbs heat (is endothermic), the temperature of the solution _____ as the solute dissolves

A

decreases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

The solubility will ________ as temperature increases (endothermic)

A

increase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

When dissolving releases heat (is exothermic), the temperature of the solution _________ as the solute dissolves

A

increases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

The solubility will ________ as temperature increases (exothermic)

A

decrease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Henry’s law

A

describes the effect of pressure on gas solubility

S = kHP

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

The solubility of a gas in a liquid is directly proportional to the

A

partial pressure of the gas above the solution.

26
Q

In general, pressure has little or no effect on

A

the solubility of solids or liquids in water.

27
Q

The solubility of a gas increases as

A

pressure increases, as illustrated at right.

28
Q

The concentration of a solute can be quantitatively expressed in several ways:

A
  1. Molarity
  2. Mass percentage of solute
  3. Molality
  4. Mole fraction
29
Q

Molarity

A

the moles of solute per liter of solution. It is abbreviated as M.

M=moles of solute/liters of solution

30
Q

Mass percentage of solute

A

is the percentage by mass of solute in a solution.

mass percentage of solute=grams of solute/grams of solution x 100

31
Q

Molality

A

the moles of solute per kilogram of solvent. It is abbreviated as m.

m=moles of solute/kilograms of solvent

32
Q

Mole fraction

A

the moles of the component over the total moles of solution. It is abbreviated X

X=moles of solute/total moles of solution

33
Q

Colligative properties

A

are properties that depend on the concentration of the solute molecules or ions in solution but not on the chemical identity of the solute

34
Q

What are the 4 colligative properties

A
  1. Vapor-pressure lowering
  2. Boiling-point elevation
  3. Freezing-point lowering
  4. Osmotic pressure
35
Q

The vapor pressure of a solution, P, is less than the vapor pressure of the

A

pure solvent, P°.

36
Q

When the solute is nonvolatile, the vapor pressure of a solution is the

A

mole fraction of the solvent times the vapor pressure of pure solvent.

37
Q

To establish an equilibrium (vapor pressure), the gaseous solvent will

A

condense in the more concentrated solution until the vapor pressures and concentrations are equal.

38
Q

vapor-pressure lowering is directly proportional to the

A

solute concentration, the definition of a colligative property

39
Q

When the solute is nonvolatile,

A

it has no appreciable vapor pressure itself and forms an ideal solution.

40
Q

When the solute is volatile

A

a nonideal solution results.

41
Q

The boiling point of a solution is higher than the boiling point of

A

pure solvent

42
Q

The freezing point of a solution is lower than the freezing point of

A

Pure solvent

43
Q

Osmosis

A

is the phenomenon of solvent flow through a semipermeable membrane to equalize the solute concentration on both sides of the membrane

44
Q

A semipermeable membrane

A

allows solvent molecules to pass through but not solute molecules

45
Q

osmotic pressure, , is equal to the pressure that, when applied,

A

just stops osmosis. Osmotic pressure is a colligative property of a solution

46
Q

Correction Factor

A

Ionic solutes dissolve to form more than one particle per formula unit. We alter the colligative property equations to account for this fact by including i, the number of ions per formula unit

47
Q

A colloid is a

A

dispersion of particles of one substance (the dispersed phase) throughout another substance or solution (the continuous phase). The dispersed particles range from 1000 pm to 200,000 pm in size—much larger than single molecules or single ions. (fog is an example)

48
Q

Colloids exhibit the Tyndall effect.

A

The path of the light is visible through a colloid because the light is reflected by the relatively larger-sized particles in the dispersed phase.

49
Q

aerosols

A

are liquid droplets or solid particles dispersed throughout a gas

50
Q

emulsion

A

consists of liquid droplets dispersed throughout another liquid (for example, particles of butterfat dispersed through homogenized milk).

51
Q

sol

A

consists of solid particles dispersed in a liquid

52
Q

Colloids in which the continuous phase is water are categorized into two major classes

A

hydrophilic colloids and hydrophobic colloids

53
Q

hydrophilic colloid

A

A colloid in which there is a strong attraction between the dispersed phase and the continuous phase (water).

54
Q

hydrophobic colloid

A

A colloid in which there is a lack of attraction between the dispersed phase and the continuous phase (water).

55
Q

Coagulation is the process by which the

A

dispersed phase of a colloid is made to aggregate and thereby separate from the continuous phase. It is analogous to precipitation from a solution.Curdled milk is an example of coagulation

56
Q

When molecules or ions that have both a hydrophobic end and a hydrophilic end are dispersed in water, they associate, or aggregate, to form colloidal-sized particles called

A

micelles

57
Q

A colloid in which the dispersed phase consists of micelles is called an

A

association colloid

58
Q

In water solution, the stearate ions associate to form micelles in which

A

the hydrocarbon ends point inward toward one another and away from the water, and ionic carboxyl groups are on the outside of the micelle facing the water

59
Q

The cleansing action of soap occurs because

A

oil and grease can be absorbed into the hydrophobic centers of soap micelles and washed away.

60
Q

The detergent molecules we have discussed so far are classified in the trade as anionics, because

A

they have a negative charge at the hydrophilic end

61
Q

Other detergent molecules are classified as cationics, because

A

they have a positive charge at the hydrophilic end