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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. What is the conjugate acid of H2PO4?
Insoluble except for nitrate and acetate
Pale yellow
H3PO4
Big K=kf/kr

2. Aromatic compounds contain what?
The benzene ring (or more correctly the phenyl group - C6H5)
Two amino acids joined together; many amino acids joined together; lots of amino acids joined together
Insoluble
Ignore 'x' if its K is very small compared to [reactant] (5% rule)

3. What part of a liquid do you look at to measure its volume?
Read the bottom of the meniscus
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.
atoms
Thermo: R=8.31J/mol/K - gas calculations: R=.0821 L atm/mol/K or 62.4L mmHg/mol/K

4. halides
Products - reactants (except for BDE when it's reactants - products)
Most are soluble except Ag - Pb
HNO3 - (nitric) H2SO4 -(sulfuric) HCl -(hydrochloric) HBr -(hydrobromic) HI - (hydroiodic) HClO4 (perchloric)
Add acid to water so that the acid doesn't boil and spit

5. What are the signs for ?G and E° for spontaneous reactions?
?G= -ve - E°= +ve
Soluble
basic
Salt - Carbon dioxide and water.(latter also known as carbonic acid H2CO3)

6. What element is used to vulcanize rubber?
Sulfur
buret - pipette - pipette filler - Erlenmeyer flask - volumetric flask
A salt solution.
NH2?

7. What is the formula of copper (II) phosphate?
Cu3(PO4)2
neutralization: high K - H2O product dissociation: low K - H2O reactant
Distillation
Iodine and CO2 (dry ice)

8. What do the 'a' and 'b' in Van Der Waal's equation allow for?
same KE - but PEice<PEwater
?G=negative - E° must be positive
They stay the same.
a-IMFs - b-molecular volume

9. How do you heat a test tube?
'non-active' metals such as Cu - Ag - Au - Pt - etc.
Heat a test tube at an angle at the side of the tube (not bottom)
[A?]/[HA] x 100 or [BH?]/[B] x 100
Cold beaker=endothermic - ?H=positive (hot beaker=exothermic - ?H=negative)

10. What is the relationship in strength between sigma and pi bonds?
PO4³?
look for changes in oxidation # - the one that goes up is oxidized and is the RA
Sigma bonds are stronger than pi bonds
[A?]/[HA] x 100 or [BH?]/[B] x 100

11. carbonates
10?8
Insoluble except group 1 and ammonium
an oxidized and reduced substance
HClO4

12. barium sulfate
RNH2
zero
White precipitate
Exothermic (?H for ANY sa/sb = -57kJ/mol)

13. copper sulfate
Heat a test tube at an angle at the side of the tube (not bottom)
blue
Graduated cylinder
OH?

14. What are hybrid orbitals used for?
Identity and purity (impure compounds usually have broad & low melting points)
Silvery gray solid - brown - purple
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
Making sigma bonds and holding lone pairs

15. Alkanes are _________ and react by _________
Saturated - Substitution (which requires more radical conditions)
RCHO (carbonyl at end)
Iodine and CO2 (dry ice)
K1 x K2

16. If a beaker gets cold - is the reaction endothermic or exothermic? is ?H positive or negative?
?G= -ve - E°= +ve
Cold beaker=endothermic - ?H=positive (hot beaker=exothermic - ?H=negative)
it is lower and occurs over less sharp a range
blue (BTB)

17. What shape is water?
Salt - Carbon dioxide and water.(latter also known as carbonic acid H2CO3)
bent
CO3²?
Anode

18. What are the prefixes used to name organic alkanes with varying number of carbon atoms? (Up to ten carbons)
Heptane
Anode
do not change
Meth - eth - prop - but - pent - hex - hept - oct - non - dec

19. What value of R do you use for thermo calculations? gas calculations?
Ksp = 4s³
Thermo: R=8.31J/mol/K - gas calculations: R=.0821 L atm/mol/K or 62.4L mmHg/mol/K
Q=It (time in seconds)
bases

20. What should you check for before you begin titrating?
C2O4²?
Evaporation
Check for air bubbles in the buret and remove the buret funnel from the buret
1. Rinse the buret/pipette with deionized water - 2. Rinse the buret/pipette with the solution you plan on filling the buret/pipette with.

21. What is the conjugate base of NH3?
NH2?
?G is zero at equilibrium when spontaneity is the same in either direction (K=1)
A) any range. b) 8-10 c) 4-6
RCOR

22. What process do you use to obtain the solute from a solution?
More chaotic (ex: gases made)
Acid spill-NaHCO3 (baking soda) base spill-acetic acid (vinegar)
Evaporation
Exothermic

23. What does saturated mean? Unsaturated?
Salt + water
Saturated organic compounds contain single bonds in their carbon skeleton. Unsaturated have at least one double or triple bond.
The Faraday or Faraday's constant.
4 sigma bonds-109° - sp³ - one double bond-120° - sp² two double bonds-180° - sp one triple bond-180° - sp

24. What process takes place at the cathode in an electrochemical cell? In an electrolytic cell?
At half equivalence - pH=pKa
Reduction always takes place at the cathode (RED CAT) In both types of cell!
Acid rain - dissolves marble buildings/statues and kills trees.
Soluble

25. What is the general formula for alkyl halides?
CrO4²?
RCOOR
RX
Transition element compounds (except if it has a full or empty d shell)

26. Ca - Sr - Ba
Insoluble except nitrate and acetate
hydroxides (ex: Ba(OH)2)
Pale purple - (orange)-yellow - red - blue - green.
Anode

27. What is the general formula for a ketone?
Combine: multiply Keq - reverse: 1/Keq - Halve coefficients: Keq^(1/2)
RCOR
Group I metals (soft metals) are stored under oil
RCOOR

28. What changes Keq?
Hg2²?
Acid spill-NaHCO3 (baking soda) base spill-acetic acid (vinegar)
RCOR
Only temperature

29. What is the difference between equivalence point and end point of a titration.
RCOOH
Distillation
No effect on Voltage (hetero) but will increase current possible (surface area increases rate of reaction)
Equivalence point is the titrant volume when the moles of acid and base are stoichiometrically equal; end point is the titrant volume when the color of the indicator permanently changes. If you choose the correct indicator - they should occur at the

30. lead compounds
Molecules with the same molecular formulas - but different structural formulas
NH2?
zero
Insoluble except nitrate and acetate

31. phosphates
CO3²?
Most INsoluble except group 1 and ammonium
Salt + water.
Only temperature

32. How do you get Ecell for spontaneous reactions?
There's one normal boiling point (1 atm) - but many boiling points (P dependent)
Trigonal pyramidal
They have high ionization energies (due to high nuclear charge and no shielding) and cannot add electrons due to full valence shell
Reverse most negative E° and add voltages to get Ecell (or take absolute difference between Ered values)

33. How many faradays of electric charge do you need to produce one mole of O2? H2?
O2 needs 4F/mol H2 needs 2F/mol
methyl formate
1) Add together a weak base with a salt of that base made with a strong acid. (or visa versa) 2) by partially neutralizing a weak base with a strong acid or weak acid with a strong base. (Ex: 0.2 mol NH3 + 0.1 mol HCl)
Combine: multiply Keq - reverse: 1/Keq - Halve coefficients: Keq^(1/2)

34. dihydrogen phosphate
CnH2n
Big K=kf/kr
H2PO4?
Glowing splint (positive result=relights)

35. How are metal oxides and hydrides bonded? are they acidic or basic?
Clear
metal oxides and hydrides are ionically bonded and basic
White precipitate
Anode

36. What is the name of S2Cl2? (Know how to name others like this - too)
Reduction always takes place at the cathode (RED CAT) In both types of cell!
R=8.31 J/mol/K
RCHO (carbonyl at end)
Disulfur dichloride

37. What is a dipeptide? polypeptide? protein?
Two amino acids joined together; many amino acids joined together; lots of amino acids joined together
ion pairing
[A?]/[HA] x 100 or [BH?]/[B] x 100
Reverse most negative E° and add voltages to get Ecell (or take absolute difference between Ered values)

38. What is Big K in terms of kf and kr?
ethers
Big K=kf/kr
Nothing
CnH2n-2

39. What do acids plus active metals form?
RCOOH
brown volatile liquid
[A?]/[HA] x 100 or [BH?]/[B] x 100
Hydrogen (active metals are metals with more negative reduction potentials in E° chart)

40. What is HCOOCH3?
r1/r2=(M2/M1)^½ - v1/v2=(T1/T2)^½ - E1/E2=T1/T2
water and substances with (s) less dense than
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
Acids; HCOOCH3 is an ester

41. What do ions and electrons travel through in a voltaic/electrolytic cell?
r1/r2=(M2/M1)^½ - v1/v2=(T1/T2)^½ - E1/E2=T1/T2
zero
'non-active' metals such as Cu - Ag - Au - Pt - etc.
Ions go through the salt bridge - electrons go through metal wires in the external circuit

42. An amphiprotic (amphoteric) species is...
Soluble
A substance that can act as an acid or a base. ex. water - HCO3? ion etc.
r1/r2=(M2/M1)^½ - v1/v2=(T1/T2)^½ - E1/E2=T1/T2
Filtration

43. What shape is carbon dioxide?
atoms
Pale purple - (orange)-yellow - red - blue - green.
n(unsaturated monomer) = polymer (no loss in material) ex. n(C2H4) = (C2H4)n (polyethylene)
linear

44. dichromate (soln + most solids)
Orange
More chaotic (ex: gases made)
zero
+4 and +2 (+4 dominates top of group and +2 at bottom of group)

45. What is the test for oxygen?
K2
CnH2n+2
Glowing splint (positive result=relights)
Alkali ion - OH? - and H2 (phenolphthalein goes pink - thus 'alkali' metals)

46. Group 14 shows non-metal and metal characteristics. What two oxidation states do the elements in group 14 exist in?
+4 and +2 (+4 dominates top of group and +2 at bottom of group)
Iodine and CO2 (dry ice)
Only temperature
RCOOR

47. What can form during the combustion of hydrocarbons in a limited supply of oxygen?
#ligands=charge x2
CO (poisonous)
Read the bottom of the meniscus
HClO4

48. Acids + Carbonates (bicarbonates) make?
Salt - Carbon dioxide and water.(latter also known as carbonic acid H2CO3)
zero-th: decreases - first: constant - second: increases
CH3COO?
Ksp = 27s4

49. When driving off water from a hydrate - how do you tell you're done?
non-metal oxides and hydrides are covalently bonded and are acidic.
Heat to constant mass-weigh - reheat - cool - and weigh again until mass is constant
No - NH3 and HCl gases are extremely soluble
Pipette (burette if need repetition)

50. What are amphoteric oxides?
Oxides that react with both acids (make salts + water) AND bases (forms complex ion - ex: ZnO and Al2O3 in bases make Zn(OH)4²? and Al(OH)4? or Al(OH)6³?)
Salt - Carbon dioxide and water.(latter also known as carbonic acid H2CO3)
H3PO4
bright yellow