AP Chemistry Test Review
Besides doing the multiple choice practice tests and free-response questions, you should know/review the
following items…
1) Give all answers to 3 sig. figs. when in doubt and label the answer correctly.
2) how to calculate the empirical formula given % composition data…(Rhyme: “% to mass, mass to mole,
divide by small, times ‘til whole.”)
3) how to determine the limiting reactant for a reaction
4) Re-memorize the list of strong acids and bases…HF is a weak acid!
5) Re-memorize the ions and their charges
6) Re-memorize the shapes of molecules: sp, sp2, sp3, sp3d, sp3d2
7) be able to draw dot notations to determine if a molecule is polar or nonpolar based on its symmetry
8) know the dot notations/shapes of these common molecules: H2O, CO2, NH3, BF3, O2, N2.
9) how to calculate the % composition by mass of a compound
10) “PTV”
PV=nRT
MM=dRT/P
(Remember the correct units needed for each variable!)
11) mole fraction & partial pressure calculations P1 =XPt
12) Graham’s Law of diffusion…given on the AP Equation Sheet
13) q=mc∆T
14) Hess’s Law
15) ∆Hrxn= ∆Hf products – ∆Hf reactants…a pure element has no ∆Hf
16) Periodic trends: atomic radius of atoms vs. ionization energy vs. electron affinity
17) calculate formal charges
18) ∆Hrxn= energy of bonds broken – energy of bonds formed
19) sigma vs. pi bonds
20) bond order calculation
21) odd # of electrons or 12 or 16 electrons are paramagnetic
22) determining the intermolecular forces in a molecule…L.D. dip-dip, H-bonds
23) interpreting phase diagrams
24) ∆T= K*m*i
25) determining the Rate Law based on lab data
26) graphs of 0, 1st, and 2nd order rate laws…[A], ln[A], 1/[A] vs. time
26) Units on the rate constant, k
27) energy “hill” diagrams…finding A.E., ∆H, effect of catalysts.
28) determine the intermediate or catalyst in a multi-step mechanism
29) Keq expressions…products/reactants…only (g) or (aq) appear!
30) Remember that K doesn’t change unless the temperature changes!
31) Le Chatlier’s principle…(+) or (-) heat; ∆P; ∆V; (+) or (-) reactants and products; inert gases have no effect.
32) Q>K…the reaction goes backwards to the reactants
33) for Ksp, Q>K means a precipitate will form (see topic #45)
34) Calculate K by doing ICE box problems
35) acid/base definitions…Bronsted-Lowry = acids donate protons; Lewis= acids accept e- pair
36) calculate pH, pOH, [H+], [OH−]
37) acid equilibrium problems…ICE box…remember pH can be used to find [H+].
38) salt pH…example: Na2CO3 = slightly basic; Al(NO3)3 = slightly acidic
39) more O’s in the oxy-acid means easier to lose the H+, therefore it is a stronger acid
40) salts made of metals in the d-block that have multiple charges are usually colorful solutions
41) common ion effect…less likely to ionize or dissolve
42) NaHCO3 is baking soda and releases CO2(g) in most reactions.
43) use H-H to solve buffer problems
44) acid base titrations MV=MV at equilibrium…be careful with Ba(OH)2 …you get 2[OH-] when in solution
45) AB2(s)  A+(aq) + 2B-(aq)
Ksp= [A][B]2 and
Ksp = (x)(2x)2
when setting up an ICE box.
46) know the signs for ∆S, ∆G, and ∆H and when each of the values are zero
47) spontaneous reactions have −∆G or + E°cell
48) ∆G° = zero for pure elements in their standard state
49) LEO- ANO; CPR-GER…how to balance redox reactions and find ox. agents or red. agents
50) calculate E°cell and be able to use the Nernst equation if not at standard conditions.
51) Electrolysis only switches the sign of the cathode and anode.
52) calculate grams or time doing a conversion problem from amps and time and 96500 C/mole e53) organic names of –ane, -ene, -yne, alcohols (-ol), ketones (-one), etc. (See “quickie review sheet”)
54) draw an isomer…same formula, but a different arrangement of the atoms
55) types of radioactive particles and their symbols: , ,  , protons, neutrons…(See “quickie review sheet”)
56) balance nuclear reactions…top and bottom #’s must be balanced on each side of the equation.
Other Stuff: 1) I suggest that you look over your AP Equations Sheet to re-familiarize yourself with what
formulas and constants are given. 2) Look over the “Writing and Predicting Chemical Reactions” review
sheet. The more reactions you practice, the better you will do, and the faster you will get. My website has a
link of tons of old chemical equations to complete from previous AP tests. 3) Look over the “Colors” review
sheet. There’s an interactive quiz on my website that you can do for practice problems. 4) Use my website
links for many more helpful hints and strategies to use.