Question 1

Calculate the pH of a solution that is 0.30 M in ammonia (NH3) and 0.20 M in ammonium chloride.
Kb, NH3 =1.76 * 10-5

Accepted Answer

The answer of Calculate the pH of a solution that...

Question 2

Which solution below would be the best choice for preparing a buffer with a pH =5.0?

Accepted Answer

A) formic acid and sodium formate, Ka = 1.8 * 10-4 
B) acetic acid and sodium acetate, Ka =1.8*10-5 
C) hypochlorous acid and sodium hypochlorite, Ka =3.5*10-8 
D) boric acid and sodium borate, Ka = 5.8 *10-10 
E) All of these solutions would be equally good choices for making this buffer. 
A) formic acid and sodium formate, Ka = 1.8 * 10-4 
B) acetic acid and sodium acetate, Ka =1.8*10-5 
C) hypochlorous acid and sodium hypochlorite, Ka =3.5*10-8 
D) boric acid and sodium borate, Ka = 5.8 *10-10 
E) All of these solutions would be equally good choices for making this buffer.

Question 3

The pKa of hydrated iron(III) is 2.5, and the pKa of hydrated nickel(II) is 10.0.If 0.1 M solutions of iron(III) nitrate and nickel(II) nitrate are constituted, which one will be the more acidic and why?

Accepted Answer

Iron(III) nitrate will be the

Question 4

A Lewis acid is

Accepted Answer

A) a proton donor. 
B) a proton acceptor. 
C) an electron-pair donor. 
D) an electron-pair acceptor. 
E) never viewed also as a Brønsted-Lowry acid. 
A) a proton donor. 
B) a proton acceptor. 
C) an electron-pair donor. 
D) an electron-pair acceptor. 
E) never viewed also as a Brønsted-Lowry acid.

Question 5

Explain how a buffer solution manages to stabilize the pH against the addition of acid, base, or additional solvent (dilution).

Accepted Answer

A buffer consists of a weak acid and its

Question 6

You wish to use precipitation to separate Br- ion from I- ions in a solution that is 0.50 M in each.You find Ksp values for the copper(I) salts are 6.3 * 10-9 for CuBr and 1.3 *10-12 for CuI at 25°C.If you are required to reduce the value of one ion to 0.10% of its original value for "complete separation," will selective precipitation by Cu+ work? Show your calculations and justify your answer.

Accepted Answer

Yes, the method will work.
CuI will prec

Question 7

A 25.00 mL sample of a hydrochloric acid solution was titrated to completion with 34.55 mL of 0.1020 M sodium hydroxide.What was the concentration of the hydrochloric acid?

Accepted Answer

A) 0.07048 M 
B) 0.1410 M 
C) 0.2819 M 
D) 0.03524 M 
E) 0.05332 M 
A) 0.07048 M 
B) 0.1410 M 
C) 0.2819 M 
D) 0.03524 M 
E) 0.05332 M

Question 8

To simulate the pH of blood, which is 7.4, a buffer solution made by dissolving sodium dihydrogen phosphate (Ka = 6.2 *10-8) and sodium hydrogen phosphate (Ka= 3.6 *10-13) together in an aqueous solution can be used.What mole ratio of Na2HPO4/NaH2PO4 is required to produce a solution with a pH of 7.4?

Accepted Answer

A) 1.2 
B) 1.6 
C) 0.90 
D) 1.0 
E) 0.96 
A) 1.2 
B) 1.6 
C) 0.90 
D) 1.0 
E) 0.96

Question 9

What will be the equilibrium concentration of silver(I) ion in an aqueous solution originally containing 0.00100 M Ag+ and 0.500 M 1,10-phenanthroline? 
Ag+(aq) + 2 phen(aq) fi [Ag(phen)2 ]1+(aq) $\quad$Kf = 1.2=1012

Accepted Answer

A) 9.0 *10-7 M 
B) 8.0 *10-13 M 
C) 6.0 *10-6 M 
D) 3.4 * 10-15 M 
E) 1.2*10-12 M 
A) 9.0 *10-7 M 
B) 8.0 *10-13 M 
C) 6.0 *10-6 M 
D) 3.4 * 10-15 M 
E) 1.2*10-12 M

Question 10

To simulate the pH of blood, which is 7.40, a buffer solution prepared by dissolving sodium dihydrogen phosphate (Ka= 6.2 *10-8) and sodium hydrogen phosphate (Ka = 3.6 * 10-13) together in an aqueous solution can be used.What mole ratio of Na2HPO4/NaH2PO4 is required to produce a solution with pH =7.40?

Accepted Answer

The answer of To simulate the pH of blood, which...

Question 11

A buffer solution is made such that the initial concentrations of lactic acid (HC3H5O3) and the lactate ion (C3H5O3-) are both 0.600 M.What is the resulting pH if 10.0 mL of 1.00 M hydrochloric acid is added to 0.500 L of the buffer solution? (The Ka of HC3H5O3 is 1.4 *10-4.)

Accepted Answer

A) 3.82 
B) 3.88 
C) 2.92 
D) 4.79 
E) 3.85 
A) 3.82 
B) 3.88 
C) 2.92 
D) 4.79 
E) 3.85

Question 12

Lead pipes were used at one time for delivering drinking water.What is the maximum possible concentration of lead in this water if it comes from lead(II) hydroxide (Ksp = 2.8 *10-16) dissolving from the surface of the pipes? Note that the EPA limit on lead in drinking water is 7.2 *10-8 M.

Accepted Answer

A) 4.1 * 10-6 M 
B) 1.6 * 10-8 M 
C) 6.5 * 10-6 M 
D) 5.1 * 10-6 M 
E) 8.3 * 10-9 M 
A) 4.1 * 10-6 M 
B) 1.6 * 10-8 M 
C) 6.5 * 10-6 M 
D) 5.1 * 10-6 M 
E) 8.3 * 10-9 M

Question 13

Which of the following salts, when dissolved in pure water, causes the greatest pH change?

Accepted Answer

A) BaCl2 
B) NaCl 
C) CuCl2 
D) FeCl3 
E) ZnCl2 
A) BaCl2 
B) NaCl 
C) CuCl2 
D) FeCl3 
E) ZnCl2

Question 14

In which of the following titrations would the solution be neutral at the equivalence point?

Accepted Answer

A) NH3 titrated with HCl 
B) Sr(OH)2 titrated with H3PO4 
C) HOCl titrated with Ba(OH)2 
D) CH3COOH titrated with NaOH 
E) HClO4 titrated with KOH 
A) NH3 titrated with HCl 
B) Sr(OH)2 titrated with H3PO4 
C) HOCl titrated with Ba(OH)2 
D) CH3COOH titrated with NaOH 
E) HClO4 titrated with KOH

Calculate the pH of a solution that is 0.30 M in ammonia (NH₃) and 0.20 M in ammonium chloride. K_b, NH₃ =1.76 * 10^-5

Which solution below would be the best choice for preparing a buffer with a pH =5.0?

The pK_a of hydrated iron(III) is 2.5, and the pK_a of hydrated nickel(II) is 10.0.If 0.1 M solutions of iron(III) nitrate and nickel(II) nitrate are constituted, which one will be the more acidic and why?

A Lewis acid is

Explain how a buffer solution manages to stabilize the pH against the addition of acid, base, or additional solvent (dilution).

A 25.00 mL sample of a hydrochloric acid solution was titrated to completion with 34.55 mL of 0.1020 M sodium hydroxide.What was the concentration of the hydrochloric acid?

A buffer solution is made such that the initial concentrations of lactic acid (HC₃H₅O₃) and the lactate ion (C₃H₅O₃-) are both 0.600 M.What is the resulting pH if 10.0 mL of 1.00 M hydrochloric acid is added to 0.500 L of the buffer solution? (The K_a of HC₃H₅O₃ is 1.4 *10^-4.)

Lead pipes were used at one time for delivering drinking water.What is the maximum possible concentration of lead in this water if it comes from lead(II) hydroxide (K_sp = 2.8 10^-16) dissolving from the surface of the pipes? Note that the EPA limit on lead in drinking water is 7.2 10^-8 M.

Which of the following salts, when dissolved in pure water, causes the greatest pH change?

In which of the following titrations would the solution be neutral at the equivalence point?

Matter and Energy an Atomic Perspective

Atoms, Ions, and Molecules the Building Blocks of Matter

Atomic Structure Explaining the Properties of Elements

Chemical Bonding Understanding Climate Change

Bonding Theories Explaining Molecular Geometry

Intermolecular Forces Attractions Between Particles

Stoichiometry Mass Relationships and Chemical Reactions

Aqueous Solutions Chemistry of the Hydrosphere

Thermochemistry Energy Changes in Chemical Reactions

Properties of Gases the Air We Breathe

Properties of Solutions Their Concentrations and Colligative Properties

Thermodynamics Why Chemical Reactions Happen

Chemical Kinetics Clearing the Air

Chemical Equilibrium Equal but Opposite Reaction Rates

Acid-Base Equilibria Proton Transfer in Biological Systems

Electrochemistry the Quest for Clean Energy

The Solid State a Particulate View

Organic Chemistry Fuels, Pharmaceuticals, and Modern Materials

Biochemistry the Compounds of Life

Nuclear Chemistry the Risks and Benefits

The Main Group Elements Life and the Periodic Table

Transition Metals Biological and Medical Applications

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Exam 16: Additional Aqueous Equilibria Chemistry and the Oceans

Calculate the pH of a solution that is 0.30 M in ammonia (NH3) and 0.20 M in ammonium chloride. Kb, NH3 =1.76 * 10-5

Which solution below would be the best choice for preparing a buffer with a pH =5.0?

The pKa of hydrated iron(III) is 2.5, and the pKa of hydrated nickel(II) is 10.0.If 0.1 M solutions of iron(III) nitrate and nickel(II) nitrate are constituted, which one will be the more acidic and why?

A Lewis acid is

Explain how a buffer solution manages to stabilize the pH against the addition of acid, base, or additional solvent (dilution).

A 25.00 mL sample of a hydrochloric acid solution was titrated to completion with 34.55 mL of 0.1020 M sodium hydroxide.What was the concentration of the hydrochloric acid?

What will be the equilibrium concentration of silver(I) ion in an aqueous solution originally containing 0.00100 M Ag+ and 0.500 M 1,10-phenanthroline? Ag+(aq) + 2 phen(aq) fi [Ag(phen)2 ]1+(aq) \quad Kf = 1.2=1012

A buffer solution is made such that the initial concentrations of lactic acid (HC3H5O3) and the lactate ion (C3H5O3-) are both 0.600 M.What is the resulting pH if 10.0 mL of 1.00 M hydrochloric acid is added to 0.500 L of the buffer solution? (The Ka of HC3H5O3 is 1.4 *10-4.)

Lead pipes were used at one time for delivering drinking water.What is the maximum possible concentration of lead in this water if it comes from lead(II) hydroxide (Ksp = 2.8 *10-16) dissolving from the surface of the pipes? Note that the EPA limit on lead in drinking water is 7.2 *10-8 M.

Which of the following salts, when dissolved in pure water, causes the greatest pH change?

In which of the following titrations would the solution be neutral at the equivalence point?

Matter and Energy an Atomic Perspective

Atoms, Ions, and Molecules the Building Blocks of Matter

Atomic Structure Explaining the Properties of Elements

Chemical Bonding Understanding Climate Change

Bonding Theories Explaining Molecular Geometry

Intermolecular Forces Attractions Between Particles

Stoichiometry Mass Relationships and Chemical Reactions

Aqueous Solutions Chemistry of the Hydrosphere

Thermochemistry Energy Changes in Chemical Reactions

Properties of Gases the Air We Breathe

Properties of Solutions Their Concentrations and Colligative Properties

Thermodynamics Why Chemical Reactions Happen

Chemical Kinetics Clearing the Air

Chemical Equilibrium Equal but Opposite Reaction Rates

Acid-Base Equilibria Proton Transfer in Biological Systems

Electrochemistry the Quest for Clean Energy

The Solid State a Particulate View

Organic Chemistry Fuels, Pharmaceuticals, and Modern Materials

Biochemistry the Compounds of Life

Nuclear Chemistry the Risks and Benefits

The Main Group Elements Life and the Periodic Table

Transition Metals Biological and Medical Applications

Filters

Calculate the pH of a solution that is 0.30 M in ammonia (NH₃) and 0.20 M in ammonium chloride. K_b, NH₃ =1.76 * 10^-5

The pK_a of hydrated iron(III) is 2.5, and the pK_a of hydrated nickel(II) is 10.0.If 0.1 M solutions of iron(III) nitrate and nickel(II) nitrate are constituted, which one will be the more acidic and why?

A buffer solution is made such that the initial concentrations of lactic acid (HC₃H₅O₃) and the lactate ion (C₃H₅O₃-) are both 0.600 M.What is the resulting pH if 10.0 mL of 1.00 M hydrochloric acid is added to 0.500 L of the buffer solution? (The K_a of HC₃H₅O₃ is 1.4 *10^-4.)

Lead pipes were used at one time for delivering drinking water.What is the maximum possible concentration of lead in this water if it comes from lead(II) hydroxide (K_sp = 2.8 10^-16) dissolving from the surface of the pipes? Note that the EPA limit on lead in drinking water is 7.2 10^-8 M.