AP CHEMISTRY FINAL EXAM REVIEW

The alkenes are compounds of carbon and hydrogen with the general formula CnH2n. If 0.561 gram of any alkene is burned in excess oxygen, what number of moles of H2O is formed? (A) 0.0400 mole (C) 0.0800 mole (B) 0.0600 mole (D) 0.400 mole

(A) 0.0400 mole

Assume that you have an "unknown" consisting of an aqueous solution of a salt that contains one of the ions listed above. Which ion must be absent on the basis of each of the following observations of the "unknown"? The solution gives no apparent reaction with dilute hydrochloric acid (A) CO3 2- (B) Cr2O7 2- (C) NH4+ (D) Ba2+ (E) Al3+

(A) CO3²-

Cu(s) + 2 Ag+ → Cu2+ + 2 Ag(s) If the equilibrium constant for the reaction above is 3.7´1015, which of the following correctly describes the standard voltage, E˚, and the standard free energy change, ∆G˚, for this reaction? (A) E˚ is positive and ∆G˚ is negative. (B) E˚ is negative and ∆G˚ is positive. (C) E˚ and ∆G˚ are both positive. (D) E˚ and ∆G˚ are both negative.

(A) E˚ is positive and ∆G˚ is negative.

Is used to etch glass chemically (A) Hydrofluoric acid (B) Carbon dioxide (C) Aluminum hydroxide (D) Ammonia (E) Hydrogen peroxide

(A) Hydrofluoric acid

Which of the following molecules has the shortest bond length? (A) N2 (B) O2 (C) Cl2 (D) Br2

(A) N2

The atom that contains exactly two unpaired electrons (A) S (B) Ca (C) Ga (D) Sb (E) Br

(A) S

The geometry of the SO3 molecule is best described as (A) trigonal planar (C) square pyramidal (B) trigonal pyramidal (D) bent

(A) trigonal planar

If 0.060 faraday is passed through an electrolytic cell containing a solution of In3+ ions, the maximum number of moles of In that could be deposited at the cathode is (A) 0.010 mole (C) 0.030 mole (B) 0.020 mole (D) 0.060 mole

(B) 0.020 mole

A sample of 9.00 grams of aluminum metal is added to an excess of hydrochloric acid. The volume of hydrogen gas produced at standard temperature and pressure is (A) 22.4 liters (C) 7.46 liters (B) 11.2 liters (D) 5.60 liters

(B) 11.2 liters

A student wishes to prepare 2.00 liters of 0.100-molar KIO3 (molecular weight 214). The proper procedure is to weigh out (A) 42.8 grams of KIO3 and add 2.00 kilograms of H2O (B) 42.8 grams of KIO3 and add H2O until the final homogeneous solution has a volume of 2.00 liters (C) 21.4 grams of KIO3 and add H2O until the final homogeneous solution has a volume of 2.00 liters (D) 42.8 grams of KIO3 and add 2.00 liters of H2O

(B) 42.8 grams of KlO3 and add H2O until the final homogeneous solution has a volume of 2.00 liters

HgO(s) + 4 I- H2O « HgI4^2- + 2 OH- ∆H < 0 Consider the equilibrium above. Which of the following changes will increase the concentration of HgI42- ? (A) Increasing the concentration of OH- (B) Adding 6 M HNO3 (C) Increasing the mass of HgO present (D) Increasing the temperature

(B) Adding 6 M HNO3

Assume that you have an "unknown" consisting of an aqueous solution of a salt that contains one of the ions listed above. Which ion must be absent on the basis of each of the following observations of the "unknown"? The solution is colorless (A) CO3 2- (B) Cr2O7 2- (C) NH4+ (D) Ba2+ (E) Al3+

(B) Cr2O7 ²-

Metallic copper is heated strongly with concentrated sulfuric acid. The products of this reaction are (A) CuSO4(s) and H2(g) only (B) Cu2+, SO2(g), and H2O (C) CuSO4(s), H2(g), and SO2(g) (D) Cu2+, SO3(g), and H2O

(B) Cu2+ , SO2 (g), and H20

The molecule with the largest dipole moment (A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3

(B) H2O

Forms monatomic ions with 2- charge in solutions (A) F (B) S (C) Mg (D) Ar (E) Mn

(B) S

Forms oxides that are common air pollutants and that yield acidic solution in water (A) F (B) S (C) Mg (D) Ar (E) Mn

(B) S

A combustion reaction (A) H2SeO4(aq) + 2 Cl-(aq) + 2 H+(aq) è H2SeO3(aq) + Cl2(g) + H2O(1) (B) S8(s) + 8 O2(g) è8 SO2(g) (C) 3 Br2(aq) + 6 OH-(aq) è 5 Br-(aq) + BrO3 -(aq) + 3 H2O(l) (D) Ca2+(aq) + SO42-(aq) èCaSO4(s) (E) PtCl4(s) + 2 Cl-(aq) è PtCl62-(aq)

(B) S8(s) + 8 O2(g)-> 8 SO2(g)

The spontaneous reaction that occurs when the cell above operates is 2 Ag+ + Cd(s) → 2 Ag(s) + Cd2+ (A) Voltage increases. (B) Voltage decreases but remains at zero. (C) Voltage becomes zero and remains at zero (D) No change in voltage occurs (E) Direction of voltage change cannot be predicted without additional information Current is allowed to flow for 5 minutes

(B) Voltage decreases but remains at zero

The spontaneous reaction that occurs when the cell above operates is 2 Ag+ + Cd(s) → 2 Ag(s) + Cd2+ A 50-milliliter sample of a 2-molar Cd(NO3)2 solution is added to the left beaker. (A) Voltage increases. (B) Voltage decreases but remains at zero. (C) Voltage becomes zero and remains at zero (D) No change in voltage occurs (E) Direction of voltage change cannot be predicted without additional information

(B) Voltage decreases but remains at zero

A reaction in which the same reactant undergoes both oxidation and reduction (A) H2SeO4(aq) + 2 Cl-(aq) + 2 H+(aq) è H2SeO3(aq) + Cl2(g) + H2O(1) (B) S8(s) + 8 O2(g) è8 SO2(g) (C) 3 Br2(aq) + 6 OH-(aq) è 5 Br-(aq) + BrO3 -(aq) + 3 H2O(l) (D) Ca2+(aq) + SO42-(aq) èCaSO4(s) (E) PtCl4(s) + 2 Cl-(aq) è PtCl62-(aq)

(C) 3 Br2(aq) + 6 OH-(aq) -> 5 Br-(aq) + BrO3

Has atmospheric properties (A) Hydrofluoric acid (B) Carbon dioxide (C) Aluminum hydroxide (D) Ammonia (E) Hydrogen peroxide

(C) Aluminum hydroxide

The atom that contains only one electron in the highest occupied energy sublevel (A) S (B) Ca (C) Ga (D) Sb (E) Br

(C) Ga

Which of the following species CANNOT function as an oxidizing agent? (A) Cr2O7 2- (B) NO3- (C) I- (D) MnO4-

(C) I-

Is purple in aqueous solution (A) PbSO4 (B) CuO (C) KMnO4 (D) KCl (E) FeCl3

(C) KMnO4

Assume that you have an "unknown" consisting of an aqueous solution of a salt that contains one of the ions listed above. Which ion must be absent on the basis of each of the following observations of the "unknown"? No odor can be detected when a sample of the solution is added drop by drop to a warm solution of sodium hydroxide (A) CO3 2- (B) Cr2O7 2- (C) NH4+ (D) Ba2+ (E) Al3+

(C) NH4⁺

The spontaneous reaction that occurs when the cell above operates is 2 Ag+ + Cd(s) → 2 Ag(s) + Cd2+ (A) Voltage increases. (B) Voltage decreases but remains at zero. (C) Voltage becomes zero and remains at zero (D) No change in voltage occurs (E) Direction of voltage change cannot be predicted without additional information The salt bridge is replaced by a platinum wire

(C) Voltage becomes zero and remains at zero

2 A(g) + B(g) « 2 C(g) When the concentration of substance B in the reaction above is doubled, all other factors being held constant, it is found that the rate of the reaction remains unchanged. The most probable explanation for this observation is that (A) the order of the reaction with respect to substance B is 1 (B) substance B is not involved in any of the steps in the mechanism of the reaction (C) substance B is not involved in the rate-determined step of the mechanism, but is involved in subsequent steps (D) substance B is probably a catalyst, and as such, its effect on the rate of the reaction does not depend on its concentration

(C) substance B is not involved in the rate-determined step of the mechanism, but is involved in subsequent steps

What number of moles of O2 is needed to produce 14.2 grams of P4O10 from P? (Molecular weight P4O10 = 284) (A) 0.0500 mole (C) 0.125 mole (B) 0.0625 mole (D) 0.250 mole

(D) 0.250 mole

When 70. milliliter of 3.0-molar Na2CO3 is added to 30. milliliters of 1.0-molar NaHCO3 the resulting concentration of Na+ is (A) 2.0 M (C) 4.0 M (B) 2.4 M (D) 4.5 M

(D) 4.5 M

Is used extensively for the production of fertilizers (A) Hydrofluoric acid (B) Carbon dioxide (C) Aluminum hydroxide (D) Ammonia (E) Hydrogen peroxide

(D) Ammonia

Assume that you have an "unknown" consisting of an aqueous solution of a salt that contains one of the ions listed above. Which ion must be absent on the basis of each of the following observations of the "unknown"? No precipitate is formed when a dilute solution of H2SO4 is added to a sample of the solution (A) CO3 2- (B) Cr2O7 2- (C) NH4+ (D) Ba2+ (E) Al3+

(D) Ba²⁺

The molecule with only one double bond (A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3

(D) C2H4

A 27.0-gram sample of an unknown hydrocarbon was burned in excess oxygen to form 88.0 grams of carbon dioxide and 27.0 grams of water. What is a possible molecular formula of the hydrocarbon? (A) CH4 (C) C4H3 (B) C2H2 (D) C4H6

(D) C4H6

A precipitation reaction (A) H2SeO4(aq) + 2 Cl-(aq) + 2 H+(aq) è H2SeO3(aq) + Cl2(g) + H2O(1) (B) S8(s) + 8 O2(g) è8 SO2(g) (C) 3 Br2(aq) + 6 OH-(aq) è 5 Br-(aq) + BrO3 -(aq) + 3 H2O(l) (D) Ca2+(aq) + SO42-(aq) èCaSO4(s) (E) PtCl4(s) + 2 Cl-(aq) è PtCl62-(aq)

(D) Ca2+(aq) + SO42-(aq) -> CaSO4(s)

What is the net ionic equation for the reaction that occurs when aqueous copper(II) sulfate is added to excess 6- molar ammonia? (A) Cu2+ + SO42- + 2 NH4+ + 2 OH- -> (NH4)2SO4 + Cu(OH)2 (B) Cu2+ + 4 NH3 + 4 H2O -> Cu(OH)4²- + 4 NH4+ (C) Cu2+ + 2 NH3 + 2 H2O -> Cu(OH)2 + 2 NH4+ (D) Cu2+ + 4 NH3 -> Cu(NH3)4²+

(D) Cu²+ + 4NH3 -> Cu(NH3)4²+

Is white and very soluble in water (A) PbSO4 (B) CuO (C) KMnO4 (D) KCl (E) FeCl3

(D) KCl

The spontaneous reaction that occurs when the cell above operates is 2 Ag+ + Cd(s) → 2 Ag(s) + Cd2+ (A) Voltage increases. (B) Voltage decreases but remains at zero. (C) Voltage becomes zero and remains at zero (D) No change in voltage occurs (E) Direction of voltage change cannot be predicted without additional information The silver electrode is made larger

(D) No change in voltage occurs

The critical temperature of a substance is the (A) temperature at which the vapor pressure of the liquid is equal to the external pressure (B) temperature at which the vapor pressure of the liquid is equal to 760 mm Hg (C) temperature at which the solid, liquid, and vapor phases are all in equilibrium (D) lowest temperature above which a substance cannot be liquefied at any applied pressure

(D) lowest temperature above which a substance cannot be liquefied at any applied pressure

Is a good oxidizing agent (A) Hydrofluoric acid (B) Carbon dioxide (C) Aluminum hydroxide (D) Ammonia (E) Hydrogen peroxide

(E) Hydrogen Peroxide

Forms a compound having the formula KXO4 (A) F (B) S (C) Mg (D) Ar (E) Mn

(E) Mn

The molecule that has the largest trigonal pyramidal (A) CO2 (B) H2O (C) CH4 (D) C2H4 (E) PH3

(E) PH3

A reaction that produces a coordination complex (A) H2SeO4(aq) + 2 Cl-(aq) + 2 H+(aq) -> H2SeO3(aq) + Cl2(g) + H2O(1) (B) S8(s) + 8 O2(g) -> 8 SO2(g) (C) 3 Br2(aq) + 6 OH-(aq) -> 5 Br-(aq) + BrO3-(aq) + 3 H2O(l) (D) Ca2+(aq) + SO42-(aq) -> CaSO4(s) (E) PtCl4(s) + 2 Cl-(aq) -> PtCl62-(aq)

(E) PtCl4(s) + 2 Cl-(aq) -> PtCl62-(aq)

Pi (π) bonding occurs in each of the following species EXCEPT (A) CO2 (B) CN- (C) CH4 (D) C2H4

(c) CH4