Physics 8

Front 1

Chemists almost always work with solutions rather than

Back 1

the pure materials.

Front 2

A solution is

Back 2

a homogeneous mixture that consists of one or more solutes uniformly
dispersed at the molecular or ionic level throughout a medium known
as the solvent. Not necessarily liquids.

Front 3

homogeneous mixture means

Back 3

that it is not possible to discern
phase boundaries between the components of the mixture

Front 4

A phase boundary

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separates regions of a mixture where the chemical or physical properties of the mixture change

Front 5

The solute is

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the material that got dissolved, and the solvent is the material that does the dissolving

Front 6

solvent is

Back 6

the material that does the dissolving

Front 7

solution is

Back 7

the whole mixture.

Front 8

Molarity, or molar concentration, is defined as

Back 8

moles of solute per liter of solution.

to give a total volume of 1.0 L,

Front 9

Molarity is abbreviated with a capital

Back 9

capital M.

Front 10

Molality, or molal concentration, expresses concentration in terms of

Back 10

expresses concentration in terms of moles of solute per kilogram of solvent.

Notice we said kilograms of solvent, not kilograms of solution.

Front 11

Molality is abbreviated with

Back 11

lower case m.

Front 12

m =

Back 12

moles of solute/
kg of solvent

Front 13

since molarity is defined as
moles of solute per liter of solution, molarity depends

Back 13

molarity depends on the temperature of the solution.

Front 14

Percent by Weight to Volume (% w/v)

Back 14

percent weight to volume is defi ned as grams of
solute per 100 milliliters of solution.

Front 15

Percent by Weight (% w/w)

Back 15

is exactly analogous to
the defi nition of percent weight to volume, except the denominator expresses
the quantity of solution in terms of grams, not milliliters.

grams of solute/total grams of solution

Front 16

Percent by Volume (% v/v)

Back 16

Percent by volume is never used in an analytical
laboratory, because volumes are not additive.

Front 17

equivalent (abbreviated Eq) is analogous to

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to a mole,

Front 18

equivalent (abbreviated Eq) is analogous to

Back 18

a mole

Front 19

normality is
analogous to

Back 19

molarity.

Front 20

Parts Per Million

Back 20

extremely dilute solutions is sometimes expressed as parts
per million.

A ppm concentration is
analogous to a percent concentration, except you are comparing the amount of
solute to a million parts of solution, rather than 100 parts.

Front 21

The solubility of a solute is

Back 21

the amount of the
solute that will dissolve in a given amount of solvent at a given temperature

Front 22

saturated solution contains

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maximum amount of a solute, as defined by its solubility.

Front 23

A supersaturated
solution contains

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more solute than allowed by the solubility of the solute

Front 24

Two liquids are miscible if they are

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are soluble in each other in all proportions.

Front 25

Oil and water,

Back 25

immiscible with each other.

One of the great “rules of thumb” in chemistry is “like dissolves like.” That
means that polar solutes are more soluble in polar solvents, while nonpolar solutes
are more soluble in nonpolar solvents.

Front 26

When a solute dissolves in a solvent, there is an

Back 26

associated energy change, and
there is often times a noticeable change in the temperature of the solution

Front 27

endothermic process,

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Energy flows into
the system

Front 28

exothermic process.

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energy flows out of the system

Front 29

solvation

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olvation involves opposite charges coming
towards each other, solvating an ion is an inherently exothermic process.

Front 30

As pressure increases, the solubility of a gaseous solute in a liquid solvent

Back 30

increases.

Front 31

Henry’s Law:

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The quantitative relationship between pressure and solubility

S = kh Pgas

Front 32

The solubility of solid and liquid solutes in liquid solvents generally increases
with

Back 32

with increasing temperature

Front 33

Temperature and the gaseous solutes in
liquid solvents

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Temperature has the opposite effect on the solubility of gaseous solutes in
liquid solvents

Front 34

There are four commonly cited colligative properties:

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1. The vapor pressure of a solution decreases with increasing solute concentration.
2. The boiling point of a solution increases with increasing solute concentration.
3. The freezing point of a solution decreases with increasing solute concentration.
4. The osmotic pressure of a solution increases with increasing solute concentration.

Front 35

The vapor pressure of a solution decreases with

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with increasing solute concentration.

Front 36

The boiling point of a solution increases with

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with increasing solute concentration.

Front 37

freezing point of a solution decreases with

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with increasing solute concentration.

Front 38

The osmotic pressure of a solution increases with

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increasing solute concentration.

Front 39

the vapor pressure of a liquid results from

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most energetic molecules near the surface of the liquid escaping into the gas
phase.

Front 40

Raoult’s Law

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the vapor pressure of a volatile component
of a solution (P) is equal to the vapor pressure of the pure substance (P°) times the mole fraction (χ) of that substance.

Front 41

vapor pressure of a volatile component
of a solution (P) is equal to the vapor pressure of the pure substance (P°) times the mole fraction (χ) of that substance.

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Raoult’s Law

Front 42

Daltons law

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the total pressures of the solution are sum of component pressures

Front 43

The total pressure of the solution will then be the sum of the component
pressures

Back 43

(Dalton’s law).

Front 44

Boiling point is defined as

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as the temperature at which the vapor pressure of the
material is equal to the ambient pressure.

Front 45

boiling point of a solution increases as

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the concentration
of solute(s) increases.

Front 46

The change in boiling point is directly proportional
to

Back 46

molal concentration of the solute particles

Front 47

ebullioscopic constant

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constant characteristic of the solvent in relationship to boiling point

Front 48

The freezing point (or melting point) of a sample is

Back 48

the temperature at which the
liquid phase of the material is in equilibrium with the solid phase

Front 49

In order to
enter into the solid state, the molecules (or ions or atoms) of the sample need to

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enter into the solid state, the molecules (or ions or atoms) of the sample need to
settle into an orderly, crystalline lattice structure.

Front 50

osmosis is

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diffusion of water through a
semipermeable membrane.

Front 51

theoretical framework to
understand the spontaneous direction of osmosis.

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second law of thermodynamics provides

Front 52

colloids are not true solutions because

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the particles in the dispersed phase are not the size of molecules or ions.

Front 53

Colloidal filtered?.

Back 53

Colloidal particles cannot be fi ltered and do not settle out of solution.