Chapter 9 General Properties of Aqueous solutions Flashcards
solution
a homogenous mixture
solute
the analyze of interest
solvent
the medium in which the solute is dissolved or dispersed
Aqueous solutions
a solution in which the water is the solvent
solubility
the maximum amount of substance that will dissolve into a solvent at a given temperature
saturated solution
a solution that contains the maximum amount of dissolve solid
electrolytes vs. non-electrolytes
once dissolved, different substances may behave differently and results in different types of solutions
electrolyte
substance that dissolve in water to form solutions that conduct electricity
non-electrolytes
substances that dissolve in water to form solutions that do not conduct electricity
electrolytes form ions there are two ways ion can be formed:
Dissociate: to separate, upon dissolving to form separate ions
ionize:the process in which a. molecular compound formed an ion
strong electrolytes
substances that dissociate or ionize completely
soluble salts, strong acids, strong bases
weak electrolytes
substances that partially dissociate or ionize
slightly soluble slats, weak acids, weak bases
conductivity
non-electrolytes: no ions-does not conduct electricity
molecular compounds(not acid/base)
strong electrolyte: lots of ions-conducts electricity very well
soluble salts
Soluble
- compounds containing an alkali metal cation(Li+,Na+,K+,Rb+,Cs+) or the ammonium ion(NH4+)
- compounds containing the nitrate ion(NO3-), acetate ion(C2H3O2-) or chlorate ion(ClO3-)
- compounds containing the chloride ion (Cl-), bromide ion(Br-), or iodide ion(I-)
exceptions: compound that contains Ag+,Hg2^2+,Pb2+ - compounds containing the sulfate ion(SO4^2-)
exceptions: compound that contains Ag+,Hg2^2+,Pb2+,Ca2+,Sr2+ or Ba2+
insoluble
- compounds containing the carbonate ion(CO3^2-) phosphate ion(PO4^3-) chromate ion(CrO4^2-) or sulfide ion(S2-)
exception: Li+, Na+,K+,Rb+,Cs+ or NH4+ - compound containing the hydroxide ion (OH-)
exception: Li+,Na+,K+,Rb+,Cs+,Ba+
molecular equation
the chemical equation that treats all species as molecules
total ionic equation
the chemical equation that explicitly shows the ions
spectator ion
ions that do not participate in the ration they appertains on both sides of the total ionic equation
acids
ability to dissolve metals. sour taste. turns litmus red
bases
slippery feel, bitter taste, turns litmus blue
acids
substances that contain H in the chemical formula and produces H+ ions when dissolved in water
bases
substances that contains OH in the chemical formula and produces OH- ion when dissolved in water
Limitations
- restricts all acid-base reactions to water
2. excludes NHg and amines as bases
acids
a proton donor
bases
a proton acceptor
Hydronium
H+ does not exist in the aqueous solution, in water, the H+ attaches to eater. H+ can be used for convenience, but it is H3O+
Acid nomenclature
acidic compounds are named as acids if it is in solution. acids are named based on whether it contains oxygen or not.
no oxygen
hydro-anion-ic acid
with oxygen
anion acid
-ite anion-ous acid
-ate anion-ic acid
polyphonic acid
acid with more than one ionizable proton
monoprotic
acids with one ionizable proton
diprotic
acids with two ionizable protons
bronzed-lowry definition
proton accepts hydroxide compounds, metal oxides, ammonia ana amines
strong acids
acids, that ionized completely
strong bases
bases that ionize completely
acid-base reactions
since acids are H+ donors and bases are H+ acceptors they are made to react together.
Redox reactions
a chemical reaction in which electrons are transferred from one substance to another
corrosion
the unwanted oxidation
4Fe + 3O2—>2Fe2O3
combustion reactions
2C8H8+25O2—->16CO2+18H20
metabolic process
C6H12O6+6O2—>6CO2+6H2O+ATP
voltaic cells
batteries
Zn+MnO2+H2O—>ZnO+Mn(OH)2
matallurgy
extraction of metals from ore
Fe2O3+3CO—>2Fe+3CO2
oxidation states
the hypothetical charge an atom would have if all bonds were ionic
rules for oxidation states
- the sum of the oxidation states must equal the net charge
- for lone elements the os=charge
- for ionic compounds, the charge of the ions are the os.
- in compounds a. F is alway -1 b. H is usually +1 c.O is usually -2
except: hydride, peroxide’s, superoxides
os
the hypothetical charge an atom would have if all bonds were ionic
reduce agent
a substance that causes another compound to be reduced, therefore itself is oxidized
oxidizing agent
a substance that cause another compound to be oxidized, therefore itself is reduced
Concentration of solutions
the amount of solute in solution can vary. one way of expressing this amount is through the unit of molarity
Molarity, M: amount of solute, mol/ volume of solution L
Dilutions
C1V1=C2V2. M1V1=M2V2
C1:mol/L
V1: L=mol initially
the amount of solute does not change when a solvent is added to dilute the solutions. but since the volume of solutions increases the concentration must decrease
pH scale
in many applications the concentration of H+ ions is important often the concentration is small.
pH=-log[H+]
auto ionization of water
process is driven by hydrogen bonding
Gravimetric analysis
analytical technique based on masses requires reactions to be completed
tritration
an analytical technique for precisely determine the concentration or amount of solute in a sample by reacting it with a standard of known concentration
equivalence point
the point in the titration in which the number of moles of titrant and moles of analyze are in stoichiometric equivalence
end point
the point in the titration in which the indicator changes color indicating the stoppage of the titration
