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 reflux?
Kc=Kp
proton acceptor.
Optical isomers contain at least one chiral (asymmetric) C atom which is a C atom that has four different groups attached to it.
boiling without losing volatile solvents/reactants


2. Is the freezing of ice endothermic or exothermic?
diamond and graphite
boiling without losing volatile solvents/reactants
Perform ICE BOX calculation based on K1
Exothermic


3. Nonmetals are good _____ agents. Metals are good _______ agents.
same KE - but PEice<PEwater
oxidizing - (F2 is the best) - reducing (ex: Li - Na).
Eudiometer
ROH


4. What changes Keq?
They decrease (or could be the same if the solid has ONLY JUST disappeared)
Only temperature
hydroxides (ex: Ba(OH)2)
MnO4?


5. ammonium
Sulfur
NO3?
it's lower and occurs over less sharp a range
NH4?


6. What is a dipeptide? polypeptide? protein?
NH4?
Salt - Carbon dioxide and water.(latter also known as carbonic acid H2CO3)
yellow
Two amino acids joined together; many amino acids joined together; lots of amino acids joined together


7. chromate ion (soln + most solids)
They stay the same.
yellow
No - it depends on the number of ions produced on dissolving.
S crystal at 0K=0


8. What is H2CO3 (carbonate acid) usually written as?
H2O + CO2 (it decomposes readily)
Synthetic condensation polymer (aka a polyamide)
Potassium permanganate and potassium dichromate (they're clues that a reaction will be redox)
zero-th: decreases - first: constant - second: increases


9. What is the general formula for an alcohol?
H2PO4?
ROH
Increases down group 1 decreases down group 17
CO3²?


10. Esters smell like _______ and amines smell like _______ and are ______.
4 sigma bonds-109° - sp³ - one double bond-120° - sp² two double bonds-180° - sp one triple bond-180° - sp
The benzene ring (or more correctly the phenyl group - C6H5)
Whether or not they can form H-bonds with water (ex: Ethyl alcohol is soluble but dimethyl ether is not)
fruit - fish - bases


11. What do you use to look at burning magnesium? why?
look for changes in oxidation # - the one that goes up is oxidized and is the RA
blue glass - it filters UV
Decant
proton acceptor.


12. What two types of substances are present in all redox reactions?
Suniverse increases for spontaneous processes
small size and high charge
A substance that can act as an acid or a base. ex. water - HCO3? ion etc.
an oxidized and reduced substance


13. sulfates
chemically (ex: with carbon)
C4H10
Q=It (time in seconds)
Soluble except Ag - Pb - Ca - Sr Ba)


14. hydroxides
acids
The one with most oxygen atoms (highest oxidation number)
RCOOR
Insoluble (except group 1 ammonium and Ba)


15. phosphate
Insoluble except group 1 and ammonium
There's one normal boiling point (1 atm) - but many boiling points (P dependent)
Silvery gray solid - brown - purple
PO4³?


16. What is the formula for summation?


17. cyanide
CN?
Acid rain - dissolves marble buildings/statues and kills trees.
Eudiometer
SO4²?


18. What is the test for hydrogen?
lighted splint (positive result=pop)
No - NH3 and HCl gases are extremely soluble
Most INsoluble except group 1 and ammonium
ethers


19. What type of solutions do small - highly charged cations tend to form?
Acidic solutions (Ex: [Fe(H2O)6]³? + H2O = Fe(H2O)5OH]²? + H3O?)
Reverse most negative E° and add voltages to get Ecell (or take absolute difference between Ered values)
Whether or not they can form H-bonds with water (ex: Ethyl alcohol is soluble but dimethyl ether is not)
Temperature increase the endothermic k more (hence increasing T moves equilibrium in the endothermic direction)


20. How are non-metal oxides and hydrides bonded? are they acidic or basic?
a-IMFs - b-molecular volume
CnH2n-2
OH- and NH3
non-metal oxides and hydrides are covalently bonded and are acidic.


21. What is the formula for alkanes?
Soluble
Clear
CnH2n+2
Decant


22. Does the electrolyte with the lowest Ksp value have to be the least soluble? Why?
ion pairing
No - it depends on the number of ions produced on dissolving.
CnH2n-2
Cold beaker=endothermic - ?H=positive (hot beaker=exothermic - ?H=negative)


23. What is the conjugate acid of H2PO4?
4 sigma bonds-109° - sp³ - one double bond-120° - sp² two double bonds-180° - sp one triple bond-180° - sp
H3PO4
buret - pipette - pipette filler - Erlenmeyer flask - volumetric flask
Sulfur


24. What apparatus do you use to separate 2 immiscible liquids?
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?)
Add acid to water so that the acid doesn't boil and spit
Separating funnel
strong acids/bases are written as H+ or OH- ions


25. If a beaker gets cold - is the reaction endothermic or exothermic? is ?H positive or negative?
Alkali ion - OH? - and H2 (phenolphthalein goes pink - thus 'alkali' metals)
Cold beaker=endothermic - ?H=positive (hot beaker=exothermic - ?H=negative)
Two forms of the same element (same Z) with different # of neutrons and similar chemical properties
T increases exponentially the proportion of molecules with E > Ea


26. What are isomers?
Molecules with the same molecular formulas - but different structural formulas
blue glass - it filters UV
?G= -ve - E°= +ve
Whether or not they can form H-bonds with water (ex: Ethyl alcohol is soluble but dimethyl ether is not)


27. What do group I/II metal oxides plus water form?
bases
Soluble except Ag - Pb - Ca - Sr Ba)
They decrease (or could be the same if the solid has ONLY JUST disappeared)
look for changes in oxidation # - the one that goes up is oxidized and is the RA


28. What do the 'a' and 'b' in Van Der Waal's equation allow for?
a-IMFs - b-molecular volume
Ions go through the salt bridge - electrons go through metal wires in the external circuit
Greenish-yellow gas
No effect on Voltage (hetero) but will increase current possible (surface area increases rate of reaction)


29. What shape is water?
blue (BTB)
bent
CrO4²?
Acid spill-NaHCO3 (baking soda) base spill-acetic acid (vinegar)


30. Do you use J or kJ for ?H - ?S - and ?G?
methyl formate
They stay the same.
Filtration
?H-kJ - ?S-J - ?G-kJ


31. What apparatus do you use to pour liquids?
an oxidized and reduced substance
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.
Primary alcohols are partially oxidized to aldehydes and then totally oxidized to acids (wine to vinegar)
Pour liquids using a funnel or down a glass rod


32. When combining half equations - what do you do to E° values when multiplying coefficients?
Nothing
ClO3?
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
R=8.31 J/mol/K


33. Is the standard entropy (S°) of an element zero?
water and substances with (s) less dense than
fractional distillation
Sigma bonds are stronger than pi bonds
But S° of element is not zero (except at 0K)


34. silver compounds
Insoluble except for nitrate and acetate
blue
left - ppt will form
PO4³?


35. State whether K is high or low and whether H2O a product or reactant for the following reactions: a) neutralization. b) dissociation in water.
zero
OH- and NH3
boiling without losing volatile solvents/reactants
neutralization: high K - H2O product dissociation: low K - H2O reactant


36. What equipment do you need for a titration?
Ksp = 4s³
10?8
Primary alcohols are partially oxidized to aldehydes and then totally oxidized to acids (wine to vinegar)
buret - pipette - pipette filler - Erlenmeyer flask - volumetric flask


37. Name 2 ways in which you can create a buffer?
Exothermic (?H for ANY sa/sb = -57kJ/mol)
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)
H+
Ions go through the salt bridge - electrons go through metal wires in the external circuit


38. Metal hydrides are _____ and form _______ and _______ when added to water
RX
buret - pipette - pipette filler - Erlenmeyer flask - volumetric flask
ionic and form hydrogen and hydroxide
No effect on Voltage (hetero) but will increase current possible (surface area increases rate of reaction)


39. Alcohols and _______ are FG isomers
ethers
Heptane
OH?
Nothing


40. Acid plus base make?
Salt + water
Only temperature
Salt + water.
Hg²?


41. perchlorate
ClO4?
Disulfur dichloride
Lack of rotation of groups around a double bond. (cis has groups on same side - trans on opposite sides)
Soluble


42. What is the general formula for a ketone?
same KE - but PEice<PEwater
look for changes in oxidation # - the one that goes up is oxidized and is the RA
zero
RCOR


43. What is the sign of the anode in voltaic cells? in electrolytic cells?
CrO4²?
An active metal.
Soluble except Ag - Pb - Ca - Sr Ba)
voltaic: - electrolytic: +


44. The oxidation # for acid base reactions...
do not change
+4 and +2 (+4 dominates top of group and +2 at bottom of group)
?G=negative - E° must be positive
C2O4²?


45. When a cell is 'flat' a.k.a 'reached equilibrium' - what is its ?G value?
ion pairing
NH4?
an oxidized and reduced substance
zero


46. Acidic gases like SO2 in the atmosphere cause what environmental problems?
?H formation of an element in standard state=0
Acid rain - dissolves marble buildings/statues and kills trees.
ethers
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.


47. Is magnesium oxide (and other main group metal oxides) likely to be acidic - basic or neutral?
T increases exponentially the proportion of molecules with E > Ea
water and substances with (s) less dense than
basic
Acids; HCOOCH3 is an ester


48. How do you dilute an acid?


49. What are the signs of ?G and E° for spontaneous reactions?
Hg²?
?G=negative - E° must be positive
Insoluble except group 1 and ammonium
Cr2O7²?


50. What do you do to Keq when you combine 2 reactions - reverse an equation - or halve coefficients?
Pipette (burette if need repetition)
Combine: multiply Keq - reverse: 1/Keq - Halve coefficients: Keq^(1/2)
a-IMFs - b-molecular volume
boiling without losing volatile solvents/reactants