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Flashcards in Ch. 8 Solutions Deck (74)
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1
Q

Composed of 2 or more pure substances.

May be Heterogeneous or Homogeneous.

A

Mixtures

2
Q

A mixture that does not have a uniform composition throughout a sample.

A

Heterogeneous

3
Q

A mixture that has a uniform composition throughout a sample.

A

Homogeneous

4
Q

A homogeneous mixture that contains small particles.

Liquid solutions are transparent. Can not be separated by filtration.

A

Solutions

5
Q

When 2 substances form a solution, the substance present in the lesser amount is called the ____

A

solute

6
Q

When 2 substances form a solution, the substance present in the larger amount is the _____

A

solvent

7
Q

A solution with water as the solvent is called an ____

A

aqueous solution

8
Q

Mixtures that contain larger particles than particles in a solution.

A

Colloids and Suspensions

9
Q

A homogeneous mixture with larger particles (1nm-1~m in diameter) often having an opaque appearance. Can not be separated by common filtration techniques.

A

Colloid

10
Q

A heterogeneous mixture that contains large particles (greater than 1~m in diameter) suspended in a liquid. Can be separated by filtration or centrifugation.

A

Suspension

11
Q

A substance that conducts electric current in water.

A

Electrolyte

12
Q

A substance that does not conduct an electric current in water.
Examples: CH3CH2OH, H2O2

A

Nonelectrolyte.

13
Q

Electrolytes can be classified as strong or weak depending on the extent that the compound _____ or forms ions.

A

Dissociates

14
Q

Dissociates completely to form ions when dissolved in water.

Example: NaCl because Na+ cation and Cl- anion
Other examples: KOH, HCl, KBr

A

Strong electrolytes

15
Q

Dissolves in water to yield largely uncharged molecules-a small fraction of the molecules form ions.

Example: Ammonia (NH3) dissolves in water and the predominant species in then NH3.
Other examples: HF, CH3CO2OH

A

Weak electrolytes

16
Q

A unit used to express the amount of each ion in a solution.

A

Equivalents (Eq)

17
Q

The # of moles of charge that a mole of ions contributes to a solution.
Give an example.

A

Equivalents such as 1 mole of K+= 1 Eq of K+ ions b/c potassium bears a +1 charge.

18
Q

How many Eq of sulfate (SO4^2-) are present in a solution that contains 3.2 moles of SO4^2-?

A

6.4 Eq SO4^2-

19
Q

The amount of solute that dissolves in a given solvent. Reported in grams of solute per 100mL of solution (g/mL)

A

Solubility

20
Q

A solution that has less than the maximum number of grams of solute

A

unsaturated

21
Q

A solution that has the maximum number of grams of solute that can dissolve.

A

saturated

22
Q

Solubility is often described in these three words…

A

“like dissolves like”

23
Q

Most ionic and polar covalent compounds are soluble in water.

A

A polar solvent

24
Q

Non-polar compounds are soluble in ____.

A

Non-polar solvent

25
Q

Water soluble compounds are ionic or are small polar molecules that can hydrogen bond with the ____

A

water solvent

26
Q

An attraction of an ion with a dipole in a molecule

A

Ion-dipole interaction

27
Q

The process of surrounding particles of a solute with solvent molecules.

A

Solvation

28
Q

____ _____ for uncharged molecules occur only with small polar molecules or those with many O or N atoms that can hydrogen bond to water.

A

Water Solubility

29
Q

When the solvation releases more energy than that required to separate particles, the overall process is_____ (heat released)

A

Exothermic

30
Q

When the separation of particles requires more energy than is released during solvation, the process is_____ (heat absorbed)

A

Endothermic

31
Q

Rule 1 of solubility of ionic compounds is: a compound is soluble if it contains one of the following cations:

A

Group 1A cations: Na+, Li+, Rb+, Cs+, K+

Ammonium NH4+

32
Q

Rule 2 of solubility of ionic compounds is: a compound is soluble if it contains one of the following anions:

A

Halide- Cl-, Br-, I-, except for salts w/ Ag+, Hg^2+, Pb^2+
Nitrate- NO3-
Acetate- CH3CO2
Sulfate- SO4^2-, except for salts w/ Ba^2+, Hg^2+, Pb^2+

33
Q

As temperature increases the solubility generally increases and is true for most ionic and molecular solids.
The solubility of gases typically decreases with increasing temperatures.
This describes what.

A

Temperature effects on solubility

34
Q

The solution contains more than the predicted max amount of solute at a given temperature.

A

Supersaturated

35
Q

This does not affect the solubility of liquids and solids but does affect the solubility of gases.

A

Pressure effects on solubility

36
Q

The solubility of a gas in a liquid is proportional to the partial pressure of the gas above the liquid.
The higher the pressure, the higher the solubility of a gas in a solvent.

A

Henry’s Law

37
Q

How much solute is dissolved in a given amount of solution.

A

Concentration

38
Q

The most common measure for a concentration is?

A

weight/volume percent (w/v %)

39
Q

Mass of solute (g)
_____________ x100%
Volume of solution (mL)

A

w/v % equation

40
Q

The number of mililiters of solute dissolved in 100mL of solution

A

Volume/Volume percent (v/v %)

41
Q

Volume of solute (mL)
____________________ x100%
Volume of solution (mL)

A

v/v % equation

42
Q

Using the percent concentration as a conversion factor

A

It’s used to relate the amount of solute to the amount of solution

43
Q

When a solution contains a very small concentration of solute, the concentration is often expressed in ___ ____ _____

A

Parts per million (ppm)

44
Q

The number of “parts” in 1,000,000 parts of solution

A

parts per million

45
Q

“parts” may be expressed in mass or volume as long as the same unit is used for both _____ and _____.

A

numerator and denominator

46
Q

Mass of Solute (g)
_______________ x10^6
Mass of Solution (g)

A

ppm equation

47
Q

Volume of Solute (mL)
__________________x 10^6
Volume of Solution (mL)

A

ppm equation

48
Q

The number of moles of solute per liter of solution and is abbreviated as M.

A

Molarity

49
Q

Moles of solute (mol)
_________________
Liters of solution (L)

mol/L

A

Molarity equation

50
Q

The addition of a solvent to decrease the concentration of the solution.

A

Dilution

51
Q

In dilution, only the solute is constant, the _____ of the solution is changed by adding the solvent.

A

Volume

52
Q

Moles of solute= Molarity x Volume

M1xV1=M2xV2

A

Dilution formula

53
Q

Properties of a solution that depend on the concentration of the solute but do not depend on its identity.

A

Colligative Properties

54
Q

A lower vapor pressure means that the solution must be heated to a higher temperature to get the vapor pressure to equal the atmospheric pressure.

A

Boiling Point Elevation

55
Q

A solute in a solution that readily escapes into the vapor phase is said to be ______

A

Volatile

56
Q

A solute in a solution that does not readily escape into the vapor phase and has a negligible vapor pressure at a given temperature is said to be ______.

A

Non volatile

57
Q

A liquid that contains a ________ solute has a higher boiling point than the solvent alone.

A

Non volatile

58
Q

One mole of any non volatile solution raises the BOILING point of one kilogram of water by ______.

A

.51 degree C.

59
Q

The presence of solute molecules makes it harder for solvents molecules to form an organized crystalline solid, this lowering the temperature at which the liquid phase becomes a solid.

A

Freezing Point Depression

60
Q

A liquid solution that contains a ________ solute has a lower freezing point that the solvent alone.

A

Non volatile

61
Q

The amount of freezing point depression depends ONLY on the____

A

Number of dissolved particles.

62
Q

One mole of any non volatile solution lowers the FREEZING point of 1 kilogram of water by _______.

A

1.86 degrees C.

63
Q

A membrane that allows small molecules to pass across, but ions and large molecules cannot.

A

Semipermeable membrane

64
Q

The passage of solvent, usually water, across a semipermeable membrane from a solution of low solute concentration to an area of higher solute concentration.

A

Osmosis

65
Q

The pressure that prevents the flow of additional solvent into a solution on one side of a semipermeable membrane.

A

Osmotic Pressure

66
Q

The greater number of _____ the greater the osmotic pressure.

A

dissolved particles.

67
Q

.1 M glucose solution is separated from .2 M glucose solution by a semipermeable membrane.
Which solution exerts a greater osmotic pressure? Why?

A

The greater the dissolved particles, the higher the osmotic pressure.
.2M has higher dissolved particles therefore it exerts the greater osmotic pressure.

68
Q

.1 M glucose solution is separated from .2 M glucose solution by a semipermeable membrane.
Which way will water flow?

A

Water will flow from less solute concentration .1 M to higher solute concentration .2 M.

69
Q

.1 M glucose solution is separated from .2 M glucose solution by a semipermeable membrane.
What is the level of 2 solutions once equilibrium is reached?

A

Since water flows into .2M solution, the height will increase on this side and decrease on the .1 M side.

70
Q

Two solutions with the same osmotic pressure are said to be____

A

Isotonic.

71
Q

Movement of water into and out of red blood cells occurs to an equal extent.

A

Isotonic solution

72
Q

More water moves into cell than diffuses out- the cell swells and can rupture. This has lowe osmotic pressure than body fluids.

A

Hypotonic solution

73
Q

More water moves out of the cell than diffuses in-the cell shrivels. This solution has a higher osmotic pressure than body fluids.

A

Hypertonic solution

74
Q

This process involves selective passage of substances across a semipermeable membrane called a dializing membrane.

A

Dialysis