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AP Chemistry 2

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. Are weak acids (and bases) written dissociated?

2. How do you heat a test tube?
NO2 and SO2 are very soluble - CO2 and O2 are somewhat soluble
Heat a test tube at an angle at the side of the tube (not bottom)
chemically (ex: with carbon)
Good catalysts - form multiple oxidation states - often paramagnetic - good structural metals - form a host of alloys (similar sized atoms) - have similar I energies (inner filling)

3. dihydrogen phosphate
H2PO4?
NO3?
Big K=kf/kr
it's lower and occurs over less sharp a range

4. Why are noble gases stable?
They have high ionization energies (due to high nuclear charge and no shielding) and cannot add electrons due to full valence shell
-Ea/R
Insoluble (except group 1 ammonium and Ba)
RCHO (carbonyl at end)

5. What measuring device would you use for very small volumes of liquids?
Pipette (burette if need repetition)
Both electrons come from the same atom (just as good as a regular bond)
WA/SB: pH>7 SA/WB: pH<7 SA/SB: pH=7
voltaic: + electrolytic: -

6. Color (absorbance) is proportional to ________
Concentration
The Faraday or Faraday's constant.
proton donor base
CnH2n+1 often designated 'R' ex C3H7 is propyl

7. When combining half equations - what do you do to E° values when multiplying coefficients?
Nothing
There's one normal boiling point (1 atm) - but many boiling points (P dependent)
0 and 14
Two forms of the same element (same Z) with different # of neutrons and similar chemical properties

8. What is the general formula for alkyl halides?
Transition element compounds (except if it has a full or empty d shell)
[A?]/[HA] x 100 or [BH?]/[B] x 100
4 sigma bonds-109° - sp³ - one double bond-120° - sp² two double bonds-180° - sp one triple bond-180° - sp
RX

9. Diphosphorus pentoxide is a typical molecular binary compound. What is its formula?
P2O5
Insoluble except for nitrate and acetate
ethers
They have high ionization energies (due to high nuclear charge and no shielding) and cannot add electrons due to full valence shell

10. What is the word equation for condensation polymerisation ?
Monomer + monomer = polymer product + a simple molecule such as water or HCl
They have high ionization energies (due to high nuclear charge and no shielding) and cannot add electrons due to full valence shell
But S° of element is not zero (except at 0K)
No effect on Voltage (hetero) but will increase current possible (surface area increases rate of reaction)

11. What is the formula for alkynes?
AgF-soluble in water - other silver halides insoluble in water - AgCl-soluble in excess ammonia - AgBr-somewhat soluble - AgI (yellow)-somewhat soluble in excess ammonia
Suniverse increases for spontaneous processes
Unsaturated - addition (ex: decolorize bromine solution)
CnH2n-2

12. Does Benzene react by addition or substitution?
Big K=kf/kr
it reacts by substitution NOT addition
Selective absorption
A salt solution.

13. What is the 'virtual' Ka for the complete dissociation of a dibasic acid?
Current - time and charge on ion (moles of e used in half cell reaction)
K1 x K2
redox reaction
Exothermic (?H for ANY sa/sb = -57kJ/mol)

14. What are the bond angles and hybridization for a carbon with 4 sigma bonds? one double bond? two double bonds? one triple bond?
Orange
Suniverse increases for spontaneous processes
Sulfur
4 sigma bonds-109° - sp³ - one double bond-120° - sp² two double bonds-180° - sp one triple bond-180° - sp

15. What type of polymer is nylon?
zero
Synthetic condensation polymer (aka a polyamide)
allow for the vapor pressure of water and make sure to level levels
10?8

16. What is a dipeptide? polypeptide? protein?
Hydrogen (active metals are metals with more negative reduction potentials in E° chart)
Most INsoluble except group 1 and ammonium
10?8
Two amino acids joined together; many amino acids joined together; lots of amino acids joined together

17. What are the signs for ?G and E° for spontaneous reactions?
?G= -ve - E°= +ve
Insoluble except for nitrate and acetate
All single: sp³ - one double: sp² - two doubles: sp - one triple: sp - two single and two lone pairs: sp³ - three single and one lone pair: sp³
Saturated - Substitution (which requires more radical conditions)

18. halides
Supercooling can occur when cooling a solvent or solution. It occurs when there's a dip and then a rise back up to the melting point on a cooling curve.
CnH2n-2
Most are soluble except Ag - Pb
Eudiometer

19. What is Ksp in terms of molar solubility ('s') for an electrolyte A2B3 A3B2?
Ksp = 108s5
allow for the vapor pressure of water and make sure to level levels
Most are soluble except Ag - Pb
bases

20. For a weak acid solution in water - Ka = 10?6 what is Kb for its conjugate base?
The compound with the lowest Ksp value.
Cold beaker=endothermic - ?H=positive (hot beaker=exothermic - ?H=negative)
Salt + water.
10?8

21. Ions are not ______.
atoms
Combine the equations for the half reactions in the non-spontaneous direction
Synthetic condensation polymer (aka a polyamide)
voltaic: + electrolytic: -

22. barium sulfate
White precipitate
water and substances with (s) less dense than
All except for lithium
They stay the same.

23. How are primary alcohols turned into acids?
Primary alcohols are partially oxidized to aldehydes and then totally oxidized to acids (wine to vinegar)
Both electrons come from the same atom (just as good as a regular bond)
Only temperature
voltaic: - electrolytic: +

24. What are the formulas for q?
Increases.
q=mc?T q=mL (or n x ?h)
All single: sp³ - one double: sp² - two doubles: sp - one triple: sp - two single and two lone pairs: sp³ - three single and one lone pair: sp³
CnH(2n+2)

25. What is the sign of the cathode in voltaic cells? in electrolytic cells?
0.10M HCl (more ions)
water and substances with (s) less dense than
Molecules with the same molecular formulas - but different structural formulas
voltaic: + electrolytic: -

26. What type of compounds are almost always colored?
S2O3²?
K2
Decant
Transition element compounds (except if it has a full or empty d shell)

27. What process do you use to obtain the solute from a solution?
Increase - the dissociation of water is endothermic so increasing T favors forward direction - thus more ions.
Identity and purity (impure compounds usually have broad & low melting points)
Evaporation
Insoluble

28. What value of R do you use for thermo calculations? gas calculations?
Tetrahedral
Thermo: R=8.31J/mol/K - gas calculations: R=.0821 L atm/mol/K or 62.4L mmHg/mol/K
Primary alcohols are partially oxidized to aldehydes and then totally oxidized to acids (wine to vinegar)
Salt + water

29. What is the third law of thermodynamics?
S crystal at 0K=0
Acidic is when [H?] > [OH?] - basic is when [H?] < [OH?] - acidic is when [H?] = [OH?]
Ppt will NOT form (unsaturated)
An active metal.

30. What is HCOOCH3?
Acids; HCOOCH3 is an ester
Soluble
S2O3²?
Cu3(PO4)2

31. If a free element is involved - what type of reaction must be involved?
Nothing
The compound with the lowest Ksp value.
redox reaction
Big K=kf/kr

32. What can form during the combustion of hydrocarbons in a limited supply of oxygen?
Anode - oxygen. Cathode - hydrogen
Greenish-yellow gas
CO (poisonous)
CrO4²?

33. When a cell is 'flat' a.k.a 'reached equilibrium' - what is its ?G value?
Hg²?
Salt + water.
[A?]/[HA] x 100 or [BH?]/[B] x 100
zero

34. acetate
Ionic compounds
linear
CH3COO?
Acid rain - dissolves marble buildings/statues and kills trees.

35. carbonates
Mention effective nuclear charge (shielding) and distance of outer electrons from the nucleus
Insoluble except group 1 and ammonium
The benzene ring (or more correctly the phenyl group - C6H5)
zero

36. What is the general formula for an amine?
K1 x K2
Add acid to water so that the acid doesn't boil and spit
Insoluble except group 1 and ammonium
RNH2

37. What is the energy you must put into a reaction to make it start called?
O2 needs 4F/mol H2 needs 2F/mol
Insoluble except for nitrate and acetate
Pour liquids using a funnel or down a glass rod
Initiation energy (NOT Ea)

38. Name some properties of Group 17
Evaporation
States related to IMF magnitude (dispersion) - iodine-silvery grey solid - chlorine-yellowish green gas - bromine-brown volatile liquid - poisonous and reactive - good oxidizing agents -
Cu3(PO4)2
There's one normal boiling point (1 atm) - but many boiling points (P dependent)

39. Esterification is...
r1/r2=(M2/M1)^½ - v1/v2=(T1/T2)^½ - E1/E2=T1/T2
acid + alcohol
Conjugate pair (one must be a weak base or acid)
S2O3²?

40. How do you get the equation for a net electrolysis reaction?
Combine the equations for the half reactions in the non-spontaneous direction
Supercooling can occur when cooling a solvent or solution. It occurs when there's a dip and then a rise back up to the melting point on a cooling curve.
A monomer with a double bond OR two monomers with an arrangement of FGs that allows them to react repeatedly with one another (ex. OH and COOH)
r1/r2=(M2/M1)^½ - v1/v2=(T1/T2)^½ - E1/E2=T1/T2

41. chromate ion (soln + most solids)
yellow
fruit - fish - bases
+4-covalent - +2-ionic
Orange

42. Nonmetals are good _____ agents. Metals are good _______ agents.
Soluble
oxidizing - (F2 is the best) - reducing (ex: Li - Na).
zero
Separating funnel

43. What type of compounds do metals/non metals form?
Ionic compounds
Current - time and charge on ion (moles of e used in half cell reaction)
The dilution effect when the solutions mix. M1V1 = M2V2
Mono; di; tri; tetra; penta; hexa.

44. Name C7H16
Salt and water
Mention effective nuclear charge (shielding) and distance of outer electrons from the nucleus
Acidified
Heptane

45. What is the test for hydrogen?
benzene has a delocalized pi ring structure
lighted splint (positive result=pop)
Cr2O7²?
But S° of element is not zero (except at 0K)

46. Does Kw increase or decrease with T? Why?
Ignore 'x' if its K is very small compared to [reactant] (5% rule)
r1/r2=(M2/M1)^½ - v1/v2=(T1/T2)^½ - E1/E2=T1/T2
Increase - the dissociation of water is endothermic so increasing T favors forward direction - thus more ions.
ionic and form hydrogen and hydroxide

47. What apparatus do you use to separate 2 immiscible liquids?
How close results are to the accepted value
Nothing
Separating funnel
[A?]/[HA] x 100 or [BH?]/[B] x 100

48. chlorate
benzene has a delocalized pi ring structure
non-metal oxides and hydrides are covalently bonded and are acidic.
Supercooling can occur when cooling a solvent or solution. It occurs when there's a dip and then a rise back up to the melting point on a cooling curve.
ClO3?

49. What is Ksp in terms of molar solubility ('s') for an electrolyte AB3 or A3B?
Ksp = 27s4
H3PO4
ROR
H2O + CO2 (it decomposes readily)

50. When can supercooling occur? What does it look like on a cooling curve?