Part 12 Flashcards
what is a polyvalent acid/base?
a species that liberates more than one acid or base equivalent per mole
what are some common polyvalent acids?
H2SO4, H3PO4, and H2CO3
be careful with dilution” problems …use normality instead of just molarity!”
are species that can act as either oxidizing or reducing agents considered to be amphoteric?
yes; they can either accept or donate a proton.
what is titration?
procedure used to determine the molarity of an acid or base
during titration, when is the equivalence point said to have been reached?
when the number of acid equivalents equals the number of base equivalents.
what are typically used as indicators during titration?
weak organic acids or bases that have different colors in their undissociated and dissociated states.
in a titration, is the end point and equivalence point the same thing?
NO! the end point is the term used to describe when the color of the indicator changes… However, in a good titration, they will be very close!
what is the pH of the equivalence point of a strong base- strong acid titration?
7
what are the two types of electrochemical cells?
galvanic and electrolytic
galvanic AKA voltaic
in which electrochemical cell do spontaneous reactions occur?
galvanic / voltaic cell
in which electrochemical cell do nonspontaneous reactions occur?
electrolytic cell
where do oxidation and reduction occur within an electrochemical cell?
electrodes
for all electrochemical cells, the electrode at which oxidation occurs is called what?
the anode
for all electrochemical cells, the electrode at which reduction occurs is called what?
cathode
a redox reaction occurring in a galvanic cell has a -/+ delta G?
negative = spontaneous
a redox reaction occurring in an electrolytic cell has a -/+ delta G?
positive = nonspontaneous
what is the net result of beta decay?
atomic number increases by 1 ; mass number stays the same
what is the result of alpha decay?
mass number decreases by 4; atomic number decreases by 2
what is the result of gamma decay?
no notable change in mass or atomic numbers
what units is molecular weight in ?
molecular mass=molecular weight
grams/mole
what is the standard enthalpy of formation of elements or diatomic molecules?
0
what is unique about the way in which NH4 bonds?
it can form ionic bonds, despite lacking a metal !
what is a network solid?
a solid held together by an extended network of covalent bonds- usually stronger than ionic bonds! ex: diamond asbestos and graphite
how do you determine rate law?
EXPERIMENTALLY! you can not just write it out like a Ksp or Keq expression! without a table you CAN NOT DETERMINE rate law!
Do transition metals have a tendency to form complex ions?
yes!! thus, a molecule containing a transition metal would likely be more soluble in NH3 than a molecule containing an alkali or alkali earth metal
what kind of solid is SiO2 and what kind of bonds does it exhibit?
silicon is a metalloid and forms a network solid; exhibits very strong si-o bonds
out of network covalent bonds (diamond), ionic bonds (KNO3), hydrogen bonds (HNOF) and london dispersion forces (CH4) which is strongest and weakest? which would have the highest and lowest boiling points?
strongest= diamond= network covalent bond = highest bp
weakest = methane = dispersion forces = lowest bp
what type of molecules are most likely to exist as single molecules?
covalent molecules- ionic compounds do not exist as single molecules, but instead in an orderly array called a crystal lattice
