Question 1

What pH range is a HOCl - NaOCl buffer effective?

Accepted Answer

A) pH 2.0 - pH 4.0 
B) pH 7.5 - pH 9.5 
C) pH 6.5 - pH 8.5 
D) pH 6.5 - pH 9.5 
E) pH 1.0 - pH 14.0 
A) pH 2.0 - pH 4.0 
B) pH 7.5 - pH 9.5 
C) pH 6.5 - pH 8.5 
D) pH 6.5 - pH 9.5 
E) pH 1.0 - pH 14.0

Question 2

For which type of titration will the pH be neutral at the equivalence point?

Accepted Answer

A) Strong acid vs.strong base. 
B) Strong acid vs.weak base. 
C) Weak acid vs.strong base. 
D) All of the above. 
E) None of the above. 
A) Strong acid vs.strong base. 
B) Strong acid vs.weak base. 
C) Weak acid vs.strong base. 
D) All of the above. 
E) None of the above.

Question 3

The solubility of Ba(NO3)2 is 130.5 g/L at 0ºC.How many moles of dissolved salt are present in 4.0 L of a saturated solution of Ba(NO3)2 at 0ºC?

Accepted Answer

Question 4

Calculate the pH of a solution that is 0.20M NH3(aq)and 0.35 M NH4Cl(aq).
(Kb(NH3)= 1.8 x 10-5)

Accepted Answer

Question 5

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed?

Accepted Answer

A) 0.10 M NH3 and 0.10 M HCl 
B) 0.10 M NH4+ and 0.10 M KOH 
C) 0.20 M NH3 0.10 M KOH 
D) 0.20 M NH3 and 0.10 M HCl 
E) 0.20 M NH4+ and 0.10M HCl 
A) 0.10 M NH3 and 0.10 M HCl 
B) 0.10 M NH4+ and 0.10 M KOH 
C) 0.20 M NH3 0.10 M KOH 
D) 0.20 M NH3 and 0.10 M HCl 
E) 0.20 M NH4+ and 0.10M HCl

Question 6

Calculate the pH of a buffer solution prepared by dissolving 0.2 mole of sodium cyanate (NaCNO)and 1.0 mole of cyanic acid (HCNO)in enough water to make 1.0 liter of solution.[Ka(HCNO)= 2.0 × 10-4]

Accepted Answer

A) 0 
B) 3.0 
C) 3.7 
D) 4.4 
E) 5.0 
A) 0 
B) 3.0 
C) 3.7 
D) 4.4 
E) 5.0

Question 7

Calculate the pH of the solution resulting from the addition of 85.0 mL of 0.35 M HCl to 30.0 mL of 0.40 M aniline (C6H5NH2).Kb (C6H5NH2)= 3.8 x 10-10

Accepted Answer

A) 1.75 
B) 0.81 
C) 4.64 
D) 4.19 
E) 9.09 
A) 1.75 
B) 0.81 
C) 4.64 
D) 4.19 
E) 9.09

Question 8

An environmental chemist obtained a 200.mL sample of lake water believed to be contaminated with a single monoprotic strong acid.Titrating this sample with a 0.0050 M NaOH(aq)required 7.3 mL of the NaOH solution to reach the endpoint.If the size of the lake can be approximated as 1.1 km long by 2.3 km wide, and has an average depth of 10.m, estimate how many moles of the strong acid are present in the lake?

Accepted Answer

4.6 × 10⁶ m

Question 9

Will a precipitate (ppt)form when 300.mL of 2.0 × 10-5 M AgNO3 are added to 200.mL of 2.5 × 10-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

Accepted Answer

A) Yes, the ppt is AgNO3(s). 
B) Yes, the ppt is NaNO3(s). 
C) Yes, the ppt is NaI(s). 
D) Yes, the ppt is AgI(s). 
E) No, a precipitate will not form. 
A) Yes, the ppt is AgNO3(s). 
B) Yes, the ppt is NaNO3(s). 
C) Yes, the ppt is NaI(s). 
D) Yes, the ppt is AgI(s). 
E) No, a precipitate will not form.

Question 10

Ammonium chloride solutions are slightly acidic, so they are better solvents than water for insoluble substances such as Ca(OH)2.Identify two reactions that when added together, give the overall reaction below, and determine Kc for the overall reaction.
Ca(OH)2(s)+ 2NH4+(aq)    
Ca2+(aq)+ 2NH3(aq)+ 2H2O
Given: Ksp for Ca(OH)2 is 4.0 × 10-8; Kb for NH3 is 1.8 × 10-5.

Accepted Answer

Ca(OH)₂(s) @#IMG-DLM& Ca²⁺(aq)+

Question 11

How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF2 at 25°C to reduce the [Pb2+] to 1.0 × 10-6 M? The Ksp for PbF2 at 25 °C is 4.0 × 10-8.

Accepted Answer

What pH range is a HOCl - NaOCl buffer effective?

For which type of titration will the pH be neutral at the equivalence point?

The solubility of Ba(NO₃)₂ is 130.5 g/L at 0ºC.How many moles of dissolved salt are present in 4.0 L of a saturated solution of Ba(NO₃)₂ at 0ºC?

Calculate the pH of a solution that is 0.20M NH₃(aq)and 0.35 M NH₄Cl(aq). (K_b(NH₃)= 1.8 x 10^-5)

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed?

Calculate the pH of a buffer solution prepared by dissolving 0.2 mole of sodium cyanate (NaCNO)and 1.0 mole of cyanic acid (HCNO)in enough water to make 1.0 liter of solution.[K_a(HCNO)= 2.0 × 10^-4]

Calculate the pH of the solution resulting from the addition of 85.0 mL of 0.35 M HCl to 30.0 mL of 0.40 M aniline (C₆H₅NH₂).K_b(C₆H₅NH₂)= 3.8 x 10^-10

Will a precipitate (ppt)form when 300.mL of 2.0 × 10^-5 M AgNO₃ are added to 200.mL of 2.5 × 10^-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF₂ at 25°C to reduce the [Pb²⁺] to 1.0 × 10^-6 M? The K_sp for PbF₂ at 25 °C is 4.0 × 10^-8.

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Reactions in Aqueous Solutions

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Quantum Theory and the Electronic Structure of Atoms

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Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Entropy Free Energy and Equilibrium

Electrochemistry

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Chemistry in the Atmosphere

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metal Chemistry and Coordination Compounds

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Exam 16: Acid-Base Equilibria and Solubility Equilibria

What pH range is a HOCl - NaOCl buffer effective?

For which type of titration will the pH be neutral at the equivalence point?

The solubility of Ba(NO3)2 is 130.5 g/L at 0ºC.How many moles of dissolved salt are present in 4.0 L of a saturated solution of Ba(NO3)2 at 0ºC?

Calculate the pH of a solution that is 0.20M NH3(aq)and 0.35 M NH4Cl(aq). (Kb(NH3)= 1.8 x 10-5)

Which of the following yields a buffer solution when equal volumes of the two solutions are mixed?

Calculate the pH of a buffer solution prepared by dissolving 0.2 mole of sodium cyanate (NaCNO)and 1.0 mole of cyanic acid (HCNO)in enough water to make 1.0 liter of solution.[Ka(HCNO)= 2.0 × 10-4]

Calculate the pH of the solution resulting from the addition of 85.0 mL of 0.35 M HCl to 30.0 mL of 0.40 M aniline (C6H5NH2).Kb (C6H5NH2)= 3.8 x 10-10

Will a precipitate (ppt)form when 300.mL of 2.0 × 10-5 M AgNO3 are added to 200.mL of 2.5 × 10-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF2 at 25°C to reduce the [Pb2+] to 1.0 × 10-6 M? The Ksp for PbF2 at 25 °C is 4.0 × 10-8.

Chemistry: the Study of Change

Atoms, Molecules, and Ions

Mass Relationships in Chemical Reactions

Reactions in Aqueous Solutions

Gases

Thermochemistry

Quantum Theory and the Electronic Structure of Atoms

Periodic Relationships Among the Elements

Chemical Bonding I: Basic Concepts

Chemical Bonding Ii: Molecular Geometry and Hybridization of Atomic Orbitals

Intermolecular Forces and Liquids and Solids

Physical Properties of Solutions

Chemical Kinetics

Chemical Equilibrium

Acids and Bases

Entropy Free Energy and Equilibrium

Electrochemistry

Nuclear Chemistry

Chemistry in the Atmosphere

Metallurgy and the Chemistry of Metals

Nonmetallic Elements and Their Compounds

Transition Metal Chemistry and Coordination Compounds

Organic Chemistry

Synthetic and Natural Organic Polymers

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The solubility of Ba(NO₃)₂ is 130.5 g/L at 0ºC.How many moles of dissolved salt are present in 4.0 L of a saturated solution of Ba(NO₃)₂ at 0ºC?

Calculate the pH of a solution that is 0.20M NH₃(aq)and 0.35 M NH₄Cl(aq). (K_b(NH₃)= 1.8 x 10^-5)

Calculate the pH of a buffer solution prepared by dissolving 0.2 mole of sodium cyanate (NaCNO)and 1.0 mole of cyanic acid (HCNO)in enough water to make 1.0 liter of solution.[K_a(HCNO)= 2.0 × 10^-4]

Calculate the pH of the solution resulting from the addition of 85.0 mL of 0.35 M HCl to 30.0 mL of 0.40 M aniline (C₆H₅NH₂).K_b(C₆H₅NH₂)= 3.8 x 10^-10

Will a precipitate (ppt)form when 300.mL of 2.0 × 10^-5 M AgNO₃ are added to 200.mL of 2.5 × 10^-9 M NaI? Answer yes or no, and identify the precipitate if there is one.

How many moles of NaF must be dissolved in 1.00 liter of a saturated solution of PbF₂ at 25°C to reduce the [Pb²⁺] to 1.0 × 10^-6 M? The K_sp for PbF₂ at 25 °C is 4.0 × 10^-8.