Polarity
determines solubility
more electroneg, more e- are
UNequally shared
polar= ____ soluble
H20
Nonpolar= ___ soluble
hexene, benzene, toluene
nonpolar
soluble in nonpolar solvents
ex. hexane, benzene, toluene
O-H bonds
polar
*more O-H , more polar
the word MISCIBLE means
soluble
ethyl acetate is
polar
w/ the truck, polar
moves
(think of a polar bear moving)
CCl4 is polar or nonpolar
nonpolar
C-H bonds are
nonpolar
*more C-H more nonpolar
How to figure out if a molecule is polar or non polar?
1. draw molecule out in lexis structure
2. in every atom draw an arrow going from less electronegative (A) atom to the more electronegative atom (B)
3. Answer the question: " if my central atom were a truck stuck in mud being pulled, would the truck move?
propane
nonpolar
ethyl acetate
polar (slightly)
solution
a uniform mixture of two or more substances
ex. table salt in water
solvent
the substance in a solution that is present in a larger amount
*on DAT usually a liquid
ex. water
solute
the substance in a solution that is present in a smaller amount
ex. salt
unsaturated
less than the maximum amount of a solute is dissolved in a solvent (clear)
saturated
the maximum amount of a solute is dissolved in a solvent (cloudy)
the amount of SOLUTE in a soln
concentration
(m and M)
Molarity (M)
moles (solute)
------------
L (solution)
W/ MOLARITY...if we know the concentration and VOL you can find mol/g of soln
true
molality (m)
moles (Solute)
-------------
kg (solvent)
to remember molarity v molality
little m b/c L comes before R
to remember (m) molality.
Karleigh SOLVEs
to remember (M) molarity
Mom Likes SOLUNtions
when solving for M and m start w/ one that does NOT have a denom
true
most ionic compounds that have any of the following are SOLUBLE in water
1. Group 1 metal cations
2. nitrate (NO??)
3. perchlorate (ClO??)
4. acetate (C?H?O??)
5. ammonium (NH??)
if something is aq it
dissolved in H2O
with aq, cut them all "in half
this separates cations from anions
most ionic compounds that have any of the following are INSOLUBLE in water
1. silver (Ag?)
2. lead (Pb�?)
3. sulfide (S�?)
4. hydroxide (OH?)
5. dimercury (Hg?�?)
6. carbonate (CO?�?)
7. phosphate (PO?�?)
solubles trump the insolubles
true
complete ionic equation
- account for all of the ions present in a reaction
- in order to write, split all aqueous compounds into their relevant ions, keep solid salts in tact
what are spectator ions
Solids are ____ soluble in higher temperature
More
melting sugar in hot coffee
increase in temp= ___ solid's solubility
incre
increase in temp= ___ in gases' solubility
decre
Gases are _____ soluble at higher temperature
LESS (opposite effect) more energy helps from escape the liquid
ex. cold coke allows more CO2 to be trapped
incre pressure= _____ gases' solbility
inc
Gases are ___ soluble at higher pressure
MORE (more pressure forces gas into liquid)
ex. glass of water compressed into liquid to allow it to dissolve more
Henry's Law
P(A)=k(H)[A]
P(A)= gas pressure in solution
k(H)= constant that differs for each gas, solvent, temperature
[A]= gas concentration in moles/liter (molarity)
*DON'T HAVE TO REMEMBER*
for henry's law just remember that
P and [A]= proportional
If you ____________ Pressure (P(A)), then it will _________________ affect and _________ the concentration
Double, Proportionally, double
gas' pressure in soln is porportional to amount of dissolved gas
true
colligative properties
properties of solution that change as you add more solute
?solute = ? freezing point
?solute = ___ FP
? freezing point
increa solute=
inc BP
freezing point
?T(F) = -?K(F)m
?T(F) = change to the liquid freezing temperature
?= Van't Hoff factor
K(F)= freezing point constant
m=solutions molality (moles of solvent/kg of solvent)
what is the main diff b/w BP and FP equation
freezing pt= (-) i
Boiling point
?T(B) = -?K(B)m
?T(B) = change to the liquid boiling temperature
i= Van't Hoff factor
K(F)= boiling point constant
m=solutions molality (moles of solvent/kg of solvent)
how to find van't off factor (i)
count the number of elements
*ex: NaCl=2, Ca(No3)2= 3
as boiling point _____________, vapor pressure __________________
? boiling point= ? vapor pressure
? boiling point= ___ Vapor pressure
? vapor pressure
osmosis
the flow of water from 1 area to another
in osmosis, only ___ can pass
water
osmosis formula
?=?MRT
?=osmotic pressure
?=van't hoff factor
R=ideal constant (0.0821 L*atm/mol*K)
T=temperature
M=molarity (n/v)