Chapter 13

Front 1

Solutions

Back 1

homogeneous (uniform mixtures)

Front 2

solute

Back 2

usually present in smaller amounts, it's dissolving

Front 3

solvent

Back 3

usually present in larger amounts, causes dissolving

--usually water but not always

Front 4

dissolution(dissolves)

Back 4

solute breaks apart into ions or molecules

Front 5

crystallize

Back 5

when dissolved solute comes out of solution and forms a solid

Front 6

dynamic equilibrium

Back 6

when the rates of these processes are equal

Front 7

Saturated solutions

Back 7

contains max amount of solute for a solvent at a specific temp

Front 8

solubility

Back 8

amount of solute needed to form a saturated solution

Front 9

unsaturated solutions

Back 9

contains less than the max amount of solute at a given temp

Front 10

supersaturated solutions

Back 10

contains more than the max amount of solute at a specific temp. to make heat add solute then cool. it is not stable. if more solute added it crystallizes until saturation reached.

Front 11

Why do solutions form?

Back 11

existing forces/bonds are broken and new ones form

Front 12

intramolecular forces

Back 12

force between atoms within a molecule

---ionic,covalent,metallic

Front 13

intermolecular forces (IMF)

Back 13

forces between atoms of seperate molecules

--london,dipole-dipole,H-bond,ion-dipole

Front 14

strength of IMF forces

Back 14

london dispersion<dipole-dipole<H-Bond<Ion-dipole<Ionic bond

Front 15

solvation

Back 15

when solute (ions or molecules) are surrounded by solvent molecules in a specific way

Front 16

Hydration

Back 16

special case of solvation in which water is the solvent

Front 17

NaCl in water

Back 17

1. break solute-solute attraction-(intra:ionic bond) Breaking requires energy (delta H solute), endothermic

2. break solute-solvent interactions (Inter:H-bond) Breaking requires energy (endothermic)

3.Must form IMF Solute-solvent interactions (inter: ion-dipole) forming gives off heat (exothermic) ---interactions increase with increased ion charge, decreased ion size

Front 18

size of IMF

Back 18

determines whether the solution is endo or exothermic

Front 19

favored solution formation

Back 19

when delta H is - (exothermic). solute-solvent particles are highly attracted to each other (they want to be together, large delta H mix). also when there is an increase in disorder(randomness) (entropy)

Front 20

unfavored solution formation

Back 20

delta H solution is endothermic- (enthalpy)

Front 21

spontaneous rxn

Back 21

happens automatically with no input of energy

Front 22

Enthalpy

Back 22

(Heat) solutions form when exothermic <0. strong solvent--solute interactions

Front 23

Entropy

Back 23

(disorder) solutions form when delta s increases. helps compensate in endothermic rxns

Front 24

polar solvents dissolve

Back 24

polar or ionic solutes

Front 25

nonpolar solvents dissolve

Back 25

nonpolar solutes

Front 26

miscible

Back 26

mixes completely

Front 27

immiscible

Back 27

doesnt mix signifigantly

Front 28

polarity in solubility

Back 28

solute solubility increases as number of polar groups increases because of more attraction sites

Front 29

liquid solubility

Back 29

solute solubility decreases as carbon chain length increases because solute is becoming more non-polar

Front 30

Gas solubility

Back 30

main force- london. therefor solubility increased with increased Mm and polarity

Front 31

pressure in solubility

Back 31

strongly affects gasses dissolved in liquids, with no effect on solids or liquids in liquids. gas solubility increases when the pressure of the gas above the solvent increases.

Front 32

Henrys law

Back 32

Sg=kPg

Sg=solubility of gas(M)

k=henrys law constant

Pg=Partial pressure of gas above solution

Front 33

temperature in solubility(Phase)

Back 33

depends on phase: with increased temp...

-solid solubility increases b/c solvent moves faster and then more able to form more solute-solvent forces

-gas solubility decreases b/c solute moves faster, more particles able to leave solvent

Front 34

temperature in solubility (Soln process)

Back 34

depends on process:

endothermic- added heat overcomes solute-solute forces, solubility increases w/ increased temp, additional heat pushes for more soln to form

exothermic-added heat overcomes solute-solvent forces, solubility decreases with increased temp, additional heat counteracts solution formation

Front 35

qualitative of concentration

Back 35

less than or equal to .1g/100g= insoluble

greater than or equal to 2g/100g= very soluble

Front 36

dilute vs. concentrated

Back 36

the more solute you have the more concentrated the soln

Front 37

Mole Fraction

Back 37

moles of A/total moles of all components

Front 38

Molarity (M)

Back 38

mol/L

easy to measure volume but changes with temp

Front 39

Molality (m)

Back 39

mol/Kg

independent of temp

Front 40

colligative property

Back 40

depends on quantity of particles(concentration important)

1.Vapor pressure lowering

2.boiling point elevation

3.Freezing point depression

4.osmotic pressure

Front 41

non-electrolytes

Back 41

dissolve as entire molecules

Front 42

strong electrolytes

Back 42

dissociate into ions. ionic- strong acid/base

Front 43

van't hoff factor (i)

Back 43

compensates for # of particles dissolved and is an estimate

NaCl doesnt actually have i=2 since some ions re-associate for short time so actual would be i=1.9

Front 44

Vapor pressure

Back 44

pressure exerted by a vapor at equilibrium

Front 45

volatile

Back 45

exhibits VP (acetone)

Front 46

Nonvolatile

Back 46

no VP (Glycerin)

Front 47

addition of non-volatile solute

Back 47

always lowers VP of solvent, solvent becomes more stabilized in liquid state producing fewer gas particles

Front 48

Raoults law

Back 48

for ideal solutions-conc low, solvent and solute have similar size/IMF

Psoln=(Xsolvent)(P(degrees)solvent)

Psoln-VP of soln (w/nonvolatile solute) and depends on total concentration of solute particles added

Xsolvent-mole fraction

P(degrees)solvent-VP of pure solvent

Front 49

boiling point

Back 49

temp at which liquid VP equals external gas pressure

Front 50

adding a nonvolatile solute to a solvent __________

the boiling point relative to that of a pure solvent

Back 50

increases (elevates)

Front 51

Freezing point

Back 51

temp at which VP of solid equals the VP of liquid

Front 52

Freezing point starts at the _________

Back 52

triple point

Front 53

adding a nonvolatile solute to a solvent __________ the freezing point relative to that of a pure solvent

Back 53

decreases

Front 54

molal boiling point elevation constant and freezing point depression constant are __________ on solvent

Back 54

dependent

Front 55

Osmosis

Back 55

net movement of solvent molecules across a semipermeable membrane

Front 56

semipermeable membrane

Back 56

allows passage of certain small molecules (water) but not large solute molecules or ions due to tiny pores

Front 57

movement always occurs from

___________----->_________ solute concentration

Back 57

less----->more

Front 58

As solvent moves, liquid levels become __________ resulting in different ________ on each end of the tube

Back 58

unequal, pressures

Front 59

Osmotic pressure (pi)

Back 59

pressure required to stop osmosis

Front 60

pi=(n/v)RT or MRT

Back 60

osmotic pressure formula

Front 61

if osmotic pressures are equal for 2 solutions, they are called _________, and osmosis _________ occur through the membrane

Back 61

isotonic, wont

Front 62

hypotonic

Back 62

solution of lower concentration

Front 63

if you place red blood cells in hypotonic solution:

Hemolysis- water_______ the cells = _____________

Back 63

enters, ruptures

Front 64

hypertonic

Back 64

solution of higher concentration

Front 65

if red blood cells placed in hypertonic solution:

Crenation-water_______ the cell=_______

Back 65

leaves,shrivel