CHE 1810
STUDY GUIDE (Page 1) EXAM 3
G.Lind
What you need to know :
CHAPTER 16
Know all strong acids and all strong bases
Common ion effect (Le Chatelier's Principle)
Acid-base titrations
Calculate the molarity of the acid in a titration of an acid with a base when V(base), M(base), and V(acid) are given
and related problems
pH curves
Calculate the pH at the equivalence point of an acid-base titration (strong-strong, weak-strong)
Calculate the volume of titrant added at the equivalence point
Determine the pKa of the weak acid titrated by a base when the pH curve is given
Solubility
Solubility product (constant) Ksp ; example : Ksp [iron(III) oxide] =
2
[Fe3+ ]eq
[O2- ]3eq
Calculate the solubility (molar, g/L etc) from Ksp
Calculate the Ksp from the solubility (molar, g/L etc)
Solubility and common ions
Solubility in pure water and in a solution in which a common ion is present
pH and solubility
Solubility at a particular pH
Ion product Q =
[Fe3+ ]2 [O2- ]3
Determine whether or not there will be a ppt when two solutions are mixed and give the formula (and name) of the ppt
Calculate when a ppt will start
Calculate which ppt will start first
CHAPTER 17
Predict whether the change in the entropy of the system is positive, zero or negative for a
process (including a chemical rxn)
Suniverse =
Ssystem +
Ssurroundings
Suniverse ³ 0
(Second Law of Thermodynamics)
G = Gibbs Free Energy
G = H – TS
Go =
Ho - T S o
at T = const
S
0
means
G =
Gsystem
D universe ³
D Gsystem £ 0
G = 0 equilibrium ; G < 0 spontaneous ;
G > 0 nonspontaneous
Determine if a rxn will be spontaneous always, never, at low T, or at high T
Determine the temperature range in which the rxn will be spontaneous
Find the temperature at which the rxn goes from nonspontaneous to spontaneous
For a rxn calculate
Ho, So , Go from table values
For a rxn calculate Go from Go =
Ho - T S o
Calculate boiling point, freezing point, sublimation point from
G =
Go + RTlnQ
Go = -RTlnK
K = exp[- Go/RT]
Calculate K from
Go and vice versa
Ho and
So values
CHE 1810
STUDY GUIDE (Page 2) EXAM 3
CHAPTER 18
Know how to name inorganic compounds (ionic, covalent), ions, and acids
Determine the oxidation number (oxidation state) of each element in a compound/ion
Determine the species oxidized, reduced, oxidizing agent, reducing agent
Determine whether a rxn is a redox rxn or not
Balance a redox rxn in acidic/basic solution
Half reactions, overall rxn including electrons
Galvanic Cell
Construct a galvanic cell from two electrodes (half reactions)
Calculate the standard cell emf
Calculate the cell emf (given concentrations and pressures of reactants and products) using the Nernst Equation
Write the cell diagram of a galvanic cell
Make a sketch of a galvanic cell
Find the anode, the cathode, the oxidation, the reduction
Find out which way a redox reaction is spontaneous
Find out if X can be oxidized by Y
There will be calculations – bring your scientific calculator
Please turn your cell phone OFF
Show all your calculations
Show your calculations with units
Report your answers with correct units and correct sig. fig.
No units = wrong units
Partial credit only when all work is shown with units
No credit for a bare answer
Because of time constraints I cannot guarantee that all subjects listed above will be on the exam
One or more end of chapter problems may be on the exam
One or more PE problems may be on the exam
There may be some multiple choice problems (like the ones on the final ACS exam) on the exam
Cheat Sheet :
One letter size sheet (front and back).
Only handwritten entries. No copies from a book taped or stapled
No end of chapter problems with solutions on the cheat sheet
No practice problems on the cheat sheet
No solutions to practice problems on the cheat sheet
Your name must be printed on the cheat sheet.
The cheat sheet must be turned in with the exam
G.Lind