AP Chem Ch 4-5 Flashcards
Hydration
Add water to something –> molecule bonds with water.
Heating, dehydration, reverses this.
Polar
Unequal distribution of charge. A net electronegative charge pointing in a direction
Solubility
The maximum amount of solute that dissolves into a solvent at equilibrium.
The measure of the amount of solute that can dissolve in a volume of solvent at a given set of conditions (temperature, pressure)
Solute
Thing being dissolved
Solvent
Thing being dissolved in – solute dissolved in the solvent.
Common solvent is water
Solubitility changes with temperature and stirring
Temperature up, solubility up
Stirring up, solubility up
Amount of solute up, solubility down- precipite
Solubility rules
See other flashcard deck
Super saturated
Helps make crystillation structure
Put solute into solvent, heat up and put lots in, then cool and makes crystal
Strong electrolytes
Soluble salts, strong acids and strong bases because they all three completely dissociate into ions when dissolved in water. Conduct electricity because of the ions
What do strong electrolytes do
100% dissolve in water. Carry an electrical current
Molarity
Number of mol / L
Moles of solute over the liters of the solution
If we have 11.5 g of NaOH and they molar mass is 40g/mol, what is the molarity when dissolved in 1.50 L of water?
11.5 g * 1 mol / 40 g = .288 mol
M = mol / L = .288/1.5 = .192 M
Completely dissociates in water
Example:
Say we have a solution of .50 M of Co(NO3)2
What is the concentration of each ion present
Co2+ –> M= .50
NO3 - –> M=.5*2=1.00
Example of dilution:
If we have 1 liter of 2.7 M of KMnO4, how could we make a 1.45 M solution and a .65 M solution?
Say we want .5 L solution of both 1.45 M and .65 M
M1V1=M2V2
2.7V = (1.45)(.5)
V= .27 L
Add .27 L of the 2.7 M solution and .23 L of water to make .5 L of the 1.45 M solution
2.7V= (.65)(.5)
V=.12 L
Add .12 L of the 2.7 M solution and .38 L of water to make .5 L of the .65M solution
What type of glassware is used to make series dilutions
Eurleymuer flask
Types of chemical reactions
Precipitation
Acid-base
Oxidation-reduction
What does silica gel dissolve/not dissolve in
Silica gel is not soluble in ethyl acetate
Aspirin solubility results
Soluble in ethyl acetate
Soluble in sodium bicarbonate
INSOLUBLE in HCl
Acetametaphine solubility results
Soluble in ethyl acetate, INSOLUBLE in sodium bicarbonate
Precipitation reaction
Formation of an insoluble substance
Filtrate –> solvent
Precipaite is formed
Example of precipaite reaction:
K2CrO4 (aq) + Ba(NO3)2 (aq)–> ?
K2CrO4 (aq) + Ba(NO3)2 (aq)–> 2KNO3 (aq) + BaCrO4 (s)
Types of formulas
Formula equation
Complete ionic equation
Net ionic equation
Formula equation
Overall reaction that includes everything going on
Comete ionic equation
Breaks down the aqueous materials into the ionic components
Net ionic equation
Cancels out the ions on both sides
Example of writing net ionic equation:
AgNO3 (aq) + KCl (aq)
AgNO3 (aq) + KCl (aq) –> AgCl (s) + KNO3 (aq)
Ag+ + NO3 - + K+ + Cl- –> AgCl(s) + K+ + NO3 –> complete ionic here
Cancel
Ag+ (aq) + Cl- (aq) –> AgCl(s)
Stoichiometry of precipitan reactions:
Example:
If we have 1.50 L of .1 M of AgNO3 and we add 8 grams of NaCl (.137 mol), what product will precipite and how much will form?
AgNO3 (aq) + NaCl (AQ) –> AgCl (s) + NaNO3 (AQ)
.1 M = x mol / 1.50 L.
X= .15 mol silver nitrate
NaCl is limiting reactant
So .137 mol of AgCl is formed, multiply by molar mass to get amount formed in grams
Arrhenius concept
Acids produce H+, bases produce OH-
Bronsted - Lowry definition
Acid is a proton donor
Base is a proton acceptor
Hydroxide with weak acid
Hydroxide is so strong as a bad that it completely reacts even with weak acids
Neutralization reactions:
What volume of .1M of HCl is required to neutralize 25 mL of a .350 M NaOH solutoon
HCl + NaOH –> H2O + NaCl (Aq)
1:1 ratio of HCl to NaOH –>
.350 M = x mol / .025 L
Get moles then need same moles of HCl and use M = mol / liter to do so