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Q:
Which of the above graphs corresponds to titration III?
A) graph (1)
B) graph (2)
C) graph (3)
D) none of the graphs
Q:
Which of the above graphs corresponds to titration II?
A) graph (1)
B) graph (2)
C) graph (3)
D) none of the graphs
Q:
Assume that the conductivity of a solution depends only on the total concentration of dissolved ions and that you measure the conductivity of three different solutions while performing titrations in which:I. 50.00 mL of 0.100 M aqueous CH3CO2H is titrated by addition of 0.100 M NaOH.II. 50.00 mL of 0.100 M aqueous NaBr is titrated by addition of 0.100 M AgNO3.III. 50.00 mL of 0.100 M aqueous CaCl2 is titrated by addition of 0.100 M Na2CO3.Which of the above graphs corresponds to titration I?A) graph (1)B) graph (2)C) graph (3)D) none of the graphs
Q:
The concentration of an aqueous solution of Fe2+ can be determined by a redox titration with aqueous bromate ion, BrO3-:Fe2+ (aq) + BrO3- (aq) + 6 H+ (aq) -> 6 Fe3+ (aq) + Br- (aq) + 3 H2O (l)Assume that the black spheres in the buret represent BrO3- ions, the gray spheres in the flask represent Fe2+ ions, the concentration of the BrO3- ions in the buret is 0.120 M, and the volumes in the buret and the flask are identical. What is the concentration of the Fe2+ in the flask, and what fraction of the BrO3- solution in the buret must be added to the flask to react with all the Fe2+ ions?A) 0.0200 M Fe2+; 1/18 of the BrO3- must be added.B) 0.0200 M Fe2+; 1/3 of the BrO3- must be added.C) 0.0400 M Fe2+; 1/18 of the BrO3- must be added.D) 0.0400 M Fe2+; 1/3 of the BrO3- must be added.
Q:
The concentration of an aqueous solution of I3- can be determined by a redox titration with aqueous sodium thiosulfate, Na2S2O3:2 S2O32- (aq) + I3- (aq) + -> S4O62- (aq) + 3 I- (aq)Assume that the black spheres in the buret represent S2O32- ions, the gray spheres in the flask represent I3- ions, the concentration of the S2O32- ions in the buret is 0.120 M, and the volumes in the buret and the flask are identical. What is the concentration of the I3- in the flask, and what fraction of the S2O32- solution in the buret must be added to the flask to react with all the I3- ions?A) 0.0400 M I3-; 1/3 of the S2O32- must be added.B) 0.0400 M I3-; 2/3 of the S2O32- must be added.C) 0.0600 M I3-; 1/3 of the S2O32- must be added.D) 0.0600 M I3-; 2/3 of the S2O32- must be added.
Q:
The concentration of an aqueous solution of NaOCl can be determined by a redox titration with iodide ion in acidic solution:OCl- (aq) + 2 I- (aq) + 2 H+ (aq) -> Cl - (aq) + I2 (aq) + H2O (l)Assume that the black spheres in the buret represent I- ions, the gray spheres in the flask represent OCl- ions, the concentration of the Iâ» ions in the buret is 0.120 M, and the volumes in the buret and the flask are identical. What is the concentration of the NaOCl in the flask, and what fraction of the I- solution in the buret must be added to the flask to react with all the OClâ» ions?A) 0.0400 M NaOCl; 1/3 of the I- must be added.B) 0.0400 M NaOCl; 2/3 of the I- must be added.C) 0.0600 M NaOCl; 1/3 of the I- must be added.D) 0.0600 M NaOCl; 2/3 of the I- must be added.
Q:
Which outcome corresponds to the reaction:H3AsO4 + 3 OH- -> 3 H2O + AsO43-?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Which outcome corresponds to the reaction:H2SO4 + 2 OH- -> 2 H2O + SO42-?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Assume that an aqueous solution of hydroxide ion, OH-, represented by unshaded spheres, is allowed to mix with a solution of an acid, HnA, represented by gray spheres. Three possible outcomes are represented by boxes (a)-(c), where the black spheres represent An-, the anion of the acid. For clarity H2O molecules are not shown.Which outcome corresponds to the reaction:HCN + OH- -> H2O + CN-?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
The following pictures represent aqueous solutions of three acids HA (A = X, Y, or Z), with water molecules omitted for clarity. Unshaded spheres represent hydrogen atoms or ions and gray spheres represent A atoms or ions. Which of the three is the strongest acid, and which is the weakest?A) HX is the strongest acid and HY is the weakest acid.B) HY is the strongest acid and HX is the weakest acid.C) HY is the strongest acid and HZ is the weakest acid.D) HZ is the strongest acid and HY is the weakest acid.
Q:
Which outcome corresponds to the combination of silver and carbonate ions:Ag+(aq) + CO32-(aq) -> ?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Which outcome corresponds to the combination of copper(II) and sulfide ions:Cu2+(aq) + S2-(aq) -> ?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Which outcome corresponds to the mixing of sodium and sulfate ions:2 Na+(aq) + SO42-(aq) -> ?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Which outcome corresponds to the combination of silver and chromate ions:Ag+(aq) + CrO42-(aq) -> ?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Which outcome corresponds to the combination of calcium and carbonate ions:Ca2+(aq) + CO32-(aq) -> ?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Assume that an aqueous solution of a cation, represented by shaded spheres, is allowed to mix with a solution of an anion, represented by unshaded spheres. Three possible outcomes are represented by boxes (a)-(c).Which outcome corresponds to the mixing of potassium and sulfide ions:2 K+(aq) + S2-(aq) -> ?A) box (a)B) box (b)C) box (c)D) none of the above
Q:
Three different substances, A2X, A2Y, and A2Z, were dissolved in water with the following results. (Water molecules are omitted for clarity.) Which of the substances is the strongest electrolyte, and which is the weakest?A) A2X is the strongest electrolyte and A2Y is the weakest electrolyte.B) A2Y is the strongest electrolyte and A2X is the weakest electrolyte.C) A2Y is the strongest electrolyte and A2Z is the weakest electrolyte.D) A2Z is the strongest electrolyte and A2Y is the weakest electrolyte.
Q:
Three different substances, A2X, A2Y, and A2Z, were dissolved in water with the following results. (Water molecules are omitted for clarity.) Which of the substances is the strongest electrolyte, and which is the weakest? A) A2X is the strongest electrolyte and A2Y is the weakest electrolyte.
B) A2Y is the strongest electrolyte and A2X is the weakest electrolyte.
C) A2Y is the strongest electrolyte and A2Z is the weakest electrolyte.
D) A2Z is the strongest electrolyte and A2Y is the weakest electrolyte.
Q:
Based on the balanced chemical equation shown below, determine the mass percent of Fe3+ in a 0.6450 gram sample of iron ore, if 22.40 mL of a 0.1000 M stannous chloride, SnCl2(aq), solution is required to completely react with the Fe3+ present in the ore sample. The chemical equation for the reaction is2 Fe3+(aq) + Sn2+(aq) -> 2 Fe2+(aq) + Sn4+(aq)A) 6.196%B) 9.697%C) 19.40%D) 38.79%
Q:
Based on the balanced chemical equation shown below, determine the molarity of a solution containing Fe2+(aq), if 40.00 mL of the Fe2+(aq) solution is required to completely react with 30.00 mL of a 0.125 M potassium bromate, KBrO3(aq), solution.The chemical equation for the reaction is6 Fe2+(aq) + BrO3-(aq) + 6 H+(aq) -> 6 Fe3+(aq) + Br-(aq) + 3 H2O(l)A) 0.0156 MB) 0.0938 MC) 0.562 MD) 1.00 M
Q:
What is the molarity of a potassium triiodide solution, KI3(aq), if 30.00 mL of the solution is required to completely react with 25.00 mL of a 0.200 M thiosulfate solution, Na2S2O3(aq)? The chemical equation for the reaction is2 S2O32-(aq) + I3-(aq) -> S4O62-(aq) + 3 I-(aq).A) 0.0833 MB) 0.120 MC) 0.167 MD) 0.333 M
Q:
Based on the balanced chemical equation shown below, what volume of 0.250 M K2S2O3(aq) is needed to completely react with 12.44 mL of 0.125 M KI3(aq)?2 S2O32-(aq) + I3-(aq) -> S4O62-(aq) + 3 I-(aq).A) 3.11 mLB) 6.22 mLC) 12.4 mLD) 49.8 mL
Q:
According to the balanced chemical equation5 H2C2O4(aq) + 2 MnO4-(aq) + 6 H+(aq) -> 10 CO2(g) + 2 Mn2+(aq) + 8 H2O(l)0.3500 grams of oxalic acid, H2C2O4 will react with ________ mL of 0.100 M potassium permanganate, KMnO4 solution.A) 15.5 mLB) 38.9 mLC) 77.7 mLD) 97.2 mL
Q:
According to the balanced chemical equation5 H2C2O4(aq) + 2 MnO4-(aq) + 6 H+(aq) -> 10 CO2(g) + 2 Mn2+(aq) + 8 H2O(l)0.3500 grams of oxalic acid, H2C2O4 will react with ________ moles of permanganate, MnO4-.A) 0.001554B) 0.003887C) 0.007774D) 0.009718
Q:
According to the balanced equation shown below, 1.00 mole of oxalic acid, H2C2O4, reacts with ________ moles of permanganate ion, MnO4-.5 H2C2O4(aq) + 2 MnO4-(aq) + 6 H+(aq) -> 10 CO2(g) + 2 Mn2+(aq) + 8 H2O(l)A) 0.400B) 1.00C) 2.00D) 2.25
Q:
What is the reduction half reaction for the chemical reaction in a basic solutionClO-(aq) + Cr(OH)4-(aq) -> CrO42-(aq) + Cl-(aq)?A) ClO-(aq) + 2 H+(aq) + 2e- -> Cl-(aq) + H2O(l)B) ClO-(aq) + H2O(l) + 2e- -> Cl-(aq) + 2 OH-(aq)C) Cr(OH)4-(aq) + 4 OH-(aq) -> CrO42-(aq) + 4 H2O(l) + 3e-D) Cr(OH)4-(aq) -> CrO42-(aq) + 4 H+(aq) + 3e-
Q:
What is the reduction half reaction for the chemical reaction in a basic solutionMn2+(aq) + 2 ClO3-(aq) + OH-(aq) -> MnO2(s) + 2 ClO2(aq) + H2O(l)?A) Mn2+(aq) + 4 OH-(aq) -> MnO2(s) + 2 H2O(l) + 2e-B) Mn2+(aq) + 2 H2O(l) -> MnO2(s) + 4 H+(aq) + 2e-C) ClO3-(aq) + H2O(l) + e- -> ClO2(aq) + 2 OH-(aq)D) ClO3-(aq) + 2 H+(aq) + e- -> ClO2(aq) + H2O(l)
Q:
What is the oxidation half reaction in the chemical reactionCr2O72-(aq) + 6 Cl-(aq) + 14 H+(aq) -> 2 Cr3+(aq) + 3 Cl2(aq) + 7 H2O(l)?A) Cr2O72-(aq) + 14 H+(aq) + 6e- -> 2 Cr3+(aq) + 7 H2O(l)B) Cr2O72-(aq) + 14 H+(aq) -> 2 Cr3+(aq) + 7 H2O(l) + 6e-C) 2 Cl-(aq) -> Cl2(aq) + 2e-D) Cl2(aq) + 2e- -> 2 Cl-(aq)
Q:
What is the oxidation half reaction in the chemical reactionZn(s) + 2 H+(aq) -> Zn2+(aq) + H2(g)?A) Zn(s) -> Zn2+(aq) + 2e-B) Zn2+(aq) + 2e- -> Zn(s)C) 2 H+(aq) + 2e- -> H2(g)D) H2(g) -> 2 H+(aq) + 2e-
Q:
Determine the number of water molecules necessary to balance the reduction half reaction of that occurs in an acidic solution.
A) 1
B) 3
C) 5
D) 7
Q:
Determine the number of water molecules necessary to balance the reduction half reaction of that occurs in an acidic solution.
A) 2
B) 4
C) 5
D) 7
Q:
Determine the number of water molecules necessary to balance the reduction half reaction of that occurs in a basic solution.
A) 2
B) 3
C) 4
D) 5
Q:
Determine the number of water molecules necessary to balance the following chemical equation___Cr2O72-(aq) + ___Cl-(aq) + ___H+(aq) -> ___Cr3+(aq) +___ Cl2(g) + ___ H2O(l).A) 3B) 5C) 7D) 14
Q:
What are the coefficients in front of BrO3-(aq) and Br-(aq) when the following equation is balanced in an acidic solution:___ BrO3-(aq) + ___ Br-(aq) -> ___ Br2(aq)?A) 1, 3B) 1, 5C) 2, 3D) 2, 5
Q:
What are the coefficients in front of Fe(s) and O3(g) when the following equation is balanced in a basic solution:___ Fe(s) + ___ O3(g) -> ___ Fe2O3(s) + ___ O2(g)?A) 2, 2B) 2, 3C) 3, 2D) 3, 4
Q:
What are the coefficients in front of NO3-(aq) and Zn(s) when the following equation is balanced in a basic solution:___ NO3-(aq) + ___ Zn(s) -> ___ Zn2+(aq) + ___ NO(g)?A) 2, 3B) 2, 5C) 3, 2D) 3, 4
Q:
What are the coefficients in front of NO3-(aq) and Cu(s) when the following redox equation is balanced in an acidic solution:___ NO3-(aq) + ___ Cu(s) -> ___ NO(g) + ___ Cu2+(aq)?A) 2, 3B) 2, 6C) 3, 4D) 3, 6
Q:
In the unbalanced equation shown below how many electrons are needed in the balanced oxidation half-reaction?C2O42- (aq) + MnO4-(aq) -> CO2(aq) + Mn2+(aq)A) 1B) 2C) 5D) 10
Q:
Which elements will not react with liquid water or with aqueous H+ ions?
A) Ag, Au, Hg, Pt
B) Ba, Ca, Li, K
C) Co, Cu, Ni, Sn
D) Cr, Fe, Mn, Zn
Q:
Which elements will not react with liquid water but will react with aqueous H+ ions?
A) Ag, Cu, Hg, Pt
B) Al, Cr, Mn, Zn
C) Ba, Ca, Li, Na
D) Ag, Au, Ca, K
Q:
Which elements will react rapidly with aqueous H+ ions and also with liquid H2O?
A) Al, Cr, Fe, Mn, Zn
B) Au, Co, Cu, Ni, Sn
C) Au, Li, K, Ni, Sn
D) Ba, Ca, Li, K, Na
Q:
Using the following sequence of reactions, determine the order of oxidizing agents (strongest to weakest)Q + U+ -> Q+ + UU + W+ -> U+ + WQ + W+ -> Q+ + W.A) Q > U > WB) W > U > QC) Q+ > U+ > W+D) W+ > U+ > Q+
Q:
Using the following sequence of reactions, determine the order of reducing agents (strongest to weakest)A + B+ -> A+ + BA + C+ -> A+ + CB + C+ -> no reaction.A) A > B > CB) A > C > BC) B > C > AD) C+ > B+ > A+
Q:
Using the following portion of the activity series for oxidation half reactionsK(s) -> K+(aq) + e-Al(s) -> Al3+(aq) + 3e-Fe(s) -> Fe2+(aq) + 2e-Sn(s) -> Sn2+(aq) + 2e-determine which pairs of reactions will occur.A) Al(s) with Fe2+(aq) and Sn(s) with K+(aq)B) Fe(s) with Al(s) and Al3+(aq) with Sn2+(aq)C) Fe(s) with Sn2+(aq) and Al(s) with Sn2+(aq)D) K(s) with Al3+(aq) and Fe(s) with Al3+(aq)
Q:
Using the following portion of the activity series for oxidation half reactionsMg(s) -> Mg2+(aq) + 2e-Zn(s) -> Zn2+(aq) + 2e-Cu(s) -> Cu2+(aq) + 2e-indicate which pairs of reactions will occur.A) Cu(s) with Zn2+(aq) and Zn(s) with Mg2+(aq)B) Mg(s) with Cu2+(aq) and Zn2+(aq) with Mg2+(aq)C) Mg(s) with Cu(s) and Zn(s) with Cu(s)D) Mg(s) with Zn2+(aq) and Zn(s) with Cu2+(aq)
Q:
Using the following portion of the activity series for oxidation half reactionsCa(s) -> Ca2+(aq) + 2e-Mg(s) -> Mg2+(aq) + 2e-Zn(s) -> Zn2+(aq) + 2e-Cu(s) -> Cu2+(aq) + 2e-determine which reaction will not occur.A) Ca(s) with Cu2+(aq)B) Ca(s) with Zn2+(aq)C) Zn(s) with Cu2+(aq)D) Zn(s) with Mg2+(aq)
Q:
Using the following portion of the activity series for oxidation half reactionsK(s) -> K+(aq) + e-Al(s) -> Al3+(aq) + 3e-Fe(s) -> Fe2+(aq) + 2e-Sn(s) -> Sn2+(aq) + 2e-determine which reaction will occur.A) Al3+(aq) with Fe(s)B) Al(s) with Sn(s)C) K+(aq) with Fe2+(aq)D) K(s) with Sn2+(aq)
Q:
Using the following portion of the activity series for oxidation half-reactions, determine which combination of reactants will result in a reaction.Na(s) -> Na+(aq) + e-Cr(s) -> Cr3+(aq) + 3e-A) Na(s) with Cr(s)B) Na(s) with Cr3+(aq)C) Na+(aq) with Cr3+(aq)D) Na+(aq) with Cr(s)
Q:
Which species functions as the reducing agent in the following reduction-oxidation reaction:ZnO(s) + C(s) -> Zn(s) + CO(g)?A) C(s)B) CO(g)C) Zn(s)D) ZnO(s)
Q:
Which species functions as the reducing agent in the following reduction-oxidation reaction:2 P(s) + 3 Br2(l) -> 2 PBr3(l)?A) Br-(aq)B) Br2(l)C) P(s)D) P3+(aq)
Q:
Which species functions as the oxidizing agent in the following reduction-oxidation reaction:5 Fe2+(aq) + MnO4-(aq) + 8 H+(aq) -> Mn2+(aq) + 5 Fe3+(aq) + 4 H2O(l)?A) Fe2+(aq)B) H+(aq)C) Mn2+(aq)D) MnO4-(aq)
Q:
Which species functions as the oxidizing agent in the following reduction-oxidation reaction:Zn(s) + Cu2+(aq) -> Cu(s) + Zn2+(aq).A) Cu(s)B) Cu2+(aq)C) Zn(s)D) Zn2+(aq)
Q:
What is the oxidation number change for the iron atom in the reaction:2 Fe2O3(s) + 3 C(s) -> 4 Fe(s) + 3 CO2(g)?A) -6B) -3C) +3D) +6
Q:
What is the oxidation number change for the manganese atom in the following unbalanced reduction half reaction:MnO4-(aq) + H+(aq) -> Mn2+(aq) + H2O(l)?A) -7B) -5C) +5D) +7
Q:
In which compound is the oxidation state of hydrogen not +1?
A) H2O
B) H2O2
C) NaH
D) Na2HSO4
Q:
In which compound is the oxidation state of oxygen not -2?A) MgOB) Li2OC) Na2O2D) Al2O3
Q:
What is the oxidation number of the oxygen atom in H2O2?
A) -2
B) -1
C) +1
D) +2
Q:
What is the oxidation number of the chromium atom in K2Cr2O7?
A) -2
B) +2
C) +6
D) +7
Q:
What is the oxidation number of the sulfur atom in H2SO4?
A) -2
B) +2
C) +4
D) +6
Q:
What is the oxidation number of the sulfur atom in S8?A) -2B) 0C) +6D) +8
Q:
By analogy with the oxoacids of sulfur, H2TeO3 would be named
A) hydrotellurous acid.
B) pertelluric acid.
C) telluric acid.
D) tellurous acid.
Q:
The chemical formula for sulfurous acid is
A) H2S(aq).
B) H2SO3(aq).
C) H2SO4(aq).
D) H2S2O7(aq).
Q:
An aqueous solution of HI is named
A) hydriodic acid.
B) hydroiodous acid.
C) iodic acid.
D) iodous acid.
Q:
a net ionic equation for the neutralization reaction of H3PO4(aq) with Ba(OH)2(aq).A) 2 H3PO4(aq) + 3 Ba(OH)2(aq) -> Ba3(PO4)2(s) + 6 H2O(l)B) 2 H3PO4(aq) + 3 Ba2+(aq) + 6 OH-(aq) -> Ba3(PO4)2(s) + 6 H2O(l)C) 6 H+(aq) + 2 PO43-(aq) + 3 Ba2+(aq) + 6 OH-(aq) -> Ba3(PO4)2(s) + 6 H2O(l)D) H+(aq) + OH-(aq) -> H2O(l)
Q:
a net ionic equation for the neutralization reaction of CH3CO2H(aq) with CsOH(aq).A) CH3CO2H(aq) + CsOH(aq) -> CH3CO2Cs(aq) + H2O(l)B) CH3CO2-(aq) + H+(aq) + Cs+(aq) + OH-(aq) -> CH3CO2-(aq) + Cs+ + H2O(l)C) CH3CO2H(aq) + Cs+(aq) + OH-(aq) -> CH3CO2Cs(s) + H2O(l)D) CH3CO2H(aq) + OH-(aq) -> CH3CO2-(aq) + H2O(l)
Q:
a net ionic equation for the neutralization reaction of HCN(aq) with NaOH(aq).A) HCN(aq) + NaOH(aq) -> NaCN(aq) + H2O(l)B) HCN(aq) + Na+(aq) + OH-(aq) -> Na+(aq) + CN-(aq) + H2O(l)C) HCN(aq) + OH-(aq) -> CN-(aq) + H2O(l)D) H+(aq) + OH-(aq) -> H2O(l)
Q:
How many H+ ions can the acid CH3CO2H donate per molecule?
A) 1
B) 2
C) 3
D) 4
Q:
How many H+ ions can the acid H3PO4 donate per molecule?
A) 0
B) 1
C) 2
D) 3
Q:
How many H+ ions can the acid, H2CO3, donate per molecule?
A) 0
B) 1
C) 2
D) 3
Q:
Which of the following is not a strong acid?
A) HF
B) HCl
C) HBr
D) HI
Q:
When dissolved in water, of HClO4, Ca(OH)2, KOH, HI, which are bases?
A) Ca(OH)2 and KOH
B) HClO4 and HI
C) only HI
D) only KOH
Q:
When dissolved in water, of HClO4, Ca(OH)2, KOH, HI, which are acids?
A) Ca(OH)2 and KOH
B) HClO4 and HI
C) only HI
D) only KOH
Q:
Which one of the following compounds behaves as an acid when dissolved in water?
A) BaO
B) CH4
C) HBr
D) KOH
Q:
Which of the following compounds is an Arrhenius base?
A) CH3OH
B) CH3CO2H
C) HOCl
D) KOH
Q:
Which of the following compounds is an Arrhenius base in water?
A) C6H12O6
B) HOClO2
C) H2SO4
D) NH3
Q:
When dissolved in water, LiOH behaves as
A) an acid that forms Li+ and OH- ions.
B) an acid that forms LiO- and H+ ions.
C) a base that forms Li+ and OH- ions.
D) a base that forms LiO- and H+ ions.
Q:
What ion is provided when Arrhenius bases dissolve in water?
A) H+
B) Na+
C) Cl-
D) OH-
Q:
Which of the following compounds is not an Arrhenius acid?
A) CH3CO2H
B) CH3NH2
C) HNO3
D) H2SO4
Q:
What reagent would distinguish between Ag+ and Fe3+?
A) NaClO3
B) NaI
C) NaNO3
D) NaOH
Q:
What reagent would distinguish between Ba2+ and Pb2+?
A) NaCl
B) NaNO3
C) Na2SO4
D) Na2S2O3