Chap 17 chem 2

What is the molar solubility of AgCl in 0.10 M NaCN if the colorless complex ion Ag(CN)2- forms? Ksp for AgCl is 1.8 × 10-10 and Kf for Ag(CN)2- is

0.050 M

What is the molar solubility of AgCl in 1.0 M K2S2O3 if the complex ion Ag(S2O3)23- forms? The Ksp for AgCl is 1.8 × 10-10 and the Kf for Ag(S2O3)23- is 2.9 x 10^13

0.50 M

What is the [CH3CO2-]/[CH3CO2H] ratio necessary to make a buffer solution with a pH of 4.44? Ka = 1.8 × 10-5 for CH3CO2H.

0.50:1

Calculate the Ksp for silver sulfate if the solubility of Ag2SO4 in pure water is 4.5 g/L.

1.2 × 10-5

What is the chromium ion concentration for a saturated solution of Cr(OH)3 if the Ksp for Cr(OH)3 is 6.7x10-31

1.26 × 10-8 M

Determine the molar solubility of PbSO4 in pure water. Ksp (PbSO4) = 1.82 × 10-8.

1.35 × 10-4 M

A 100.0 mL sample of 0.10 M NH3 is titrated with 0.10 M HNO3. Determine the pH of the solution after the addition of 150.0 mL of HNO3. The Kb of NH3 is 1.8 × 10-5.

1.70

Determine the molar solubility of BaF2 in pure water. Ksp for BaF2 = 2.45 × 10-5.

1.83 × 10-2 M

What is the pH of a solution made by mixing 30.00 mL of 0.10 M HCl with 40.00 mL of 0.10 M KOH? Assume that the volumes of the solutions are additive.

12.15

What is the silver ion concentration for a saturated solution of Ag2CO3 if the Ksp for Ag2CO3 is 8.4 x 10-12

2.56 × 10-4 M

Determine the molar solubility of MgCO3 in pure water. Ksp (MgCO3) = 6.82 × 10-6.

2.61 × 10-3 M

What volume of 5.00 × 10-3 M HNO3 is needed to titrate 100.00 mL of 5.00 × 10-3 M Ca(OH)2 to the equivalence point?

200. mL

A 1.00 L buffer solution is 0.250 M in HF and 0.250 M in NaF. Calculate the pH of the solution after the addition of 100.0 mL of 1.00 M HCl. The Ka for HF is 3.5 × 10-4.

3.09

What is the molar solubility of CaF2 in 0.10 M NaF solution at 25°C? The Ksp for CaF2 is

3.4 × 10-9 M

Calculate the pH of a solution formed by mixing 250.0 mL of 0.15 M HCHO2 with 100.0 mL of 0.20 M LiCHO2. The Ka for HCHO2 is 1.8 × 10-4.

3.47

Determine the molar solubility of AgBr in a solution containing 0.200 M NaBr. Ksp (AgBr) = 7.7 × 10-13.

3.8 × 10-12 M

One liter of a saturated solution of CaF2 contains 0.0167 g of dissolved CaF2. What is the Ksp for CaF2?

3.9 × 10-11

Determine the molar solubility of Pb(IO3)2 in pure water. Ksp for Pb(IO3)2 = 2.60 × 10-13.

4.02 × 10-5 M

0.10 M potassium chromate is slowly added to a solution containing 0.20 M AgNO3 and 0.20 M Ba(NO3)2. What is the Ag+ concentration when BaCrO4 just starts to precipitate? Ksp for Ag2CrO4 and BaCrO4 are 1.1 × 10-12 and 1.2 × 10-10, respectively.

4.3 × 10-2 M

What is the pH of a solution prepared by mixing 25.00 mL of 0.10 M CH3CO2H with 25.00 mL of 0.050 M CH3CO2Na? Assume that the volume of the solutions are additive and that Ka = 1.8 × 10-5 for CH3CO2H.

4.44

Calculate the pH of a buffer that is 0.225 M HC2H3O2 and 0.162 M KC2H3O2. The Ka for HC2H3O2 is 1.8 × 10-5.

4.60

Determine the molar solubility of AgBr in a solution containing 0.150 M NaBr. Ksp (AgBr) = 7.7 × 10-13.

5.1 × 10-12 M

What is the molar solubility of Mg(OH)2 in a basic solution with a pH of 12.00? Ksp for Mg(OH)2 is 5.6 x 10-12

5.6 × 10-8 M

Calculate the molar solubility of thallium(I) chloride in 0.30 M NaCl at 25°C. Ksp for TlCl is 1.7 x10-4

5.7 × 10-4 M

One liter of a saturated solution of MgF2 contains 0.0726 g of dissolved MgF2. What is the Ksp for MgF2?

6.3 × 10-9

A buffer solution is prepared by dissolving 27.22 g of KH2PO4 and 3.37 g of KOH in enough water to make 0.100 L of solution. What is the pH of the H2PO4-/HPO42- buffer if the

6.84

Calculate the pH of a solution formed by mixing 200.0 mL of 0.30 M HClO with 100.0 mL of 0.20 M KClO. The Ka for HClO is 2.9 × 10-8.

7.06

What is the pH of a buffered system made by dissolving 17.42 g of KH2PO4 and 20.41 g of K2HPO4 in water to give a volume of 200.0 mL? The Ka2 for dihydrogen phosphate is 6.2 × 10-8 and the equilibrium reaction of interest is H2PO4-(aq)+ H2Ol = H3O+aq + HPO4-(aq)

7.17

A buffer solution is prepared by dissolving 0.200 mol of NaH2PO4 and 0.100 mol of NaOH in enough water to make 1.00 L of solution. What is the pH of the H2PO4-/HPO42- buffer if the Ka2= 6.2 x10-8

7.21

Calculate the pH of a solution formed by mixing 100.0 mL of 0.20 M HClO with 200.0 mL of 0.30 M KClO. The Ka for HClO is 2.9 × 10-8.

8.01

Calculate the pH of a buffer that is 0.200 M H3BO3 and 0.122 M KH2BO3. The Ka for H3BO3 is 5.8 × 10-10.

9.02

If a chemist wishes to prepare a buffer that will be effective at a pH of 3.00 at 25°C, the best choice would be an acid component with a Ka equal to

9.10 × 10-4.

Determine the molar solubility of AgI in pure water. Ksp (AgI) = 8.51 × 10-17.

9.22 × 10-9 M

What is the hydronium ion concentration in a solution prepared by mixing 50.00 mL of 0.10 M HCN with 50.00 mL of 0.050 M NaCN? Assume that the volumes of the solutions are additive and that Ka = 4.9 × 10-10 for HCN.

9.8 × 10-10 M

Which of the following is TRUE?

A buffer is most resistant to pH change when [acid] = [conjugate base]

Which pair of ions can be separated by the addition of chloride ion?

Ag+ and Co2+

Which metal ions can be precipitated out of solution as chlorides?

Ag+, Hg22+, Pb2+

What is the most soluble salt of the following set?

Ba(OH)2 with Ksp = 5.0 × 10-3

Define buffer capacity.

Buffer capacity is the amount of acid or base that can be added to a buffer without destroying its effectiveness.

Which statement about buffers is true?

Buffers resist change in pH upon addition of small amounts of strong acid or strong base.

Which of these neutralization reactions has a pH > 7 when equal moles of acid and base are mixed.

CH3CO2H(aq) + NaOH(aq) ⇌ H2O(l) + NaCH3CO2(aq)

Which set of ions precipitate as sulfides?

Cu2+, Pb2+, Sn2+

Which is a net ionic equation for the neutralization reaction of a strong acid with a weak base?

H3O+(aq) + NH3(aq) ⇌ NH4+(aq) + H2O(l)

Which of these neutralization reactions has a pH < 7 when equal molar amounts of acid and base are mixed.

HCl(aq) + C5H5N(aq) ⇌ C5H5NHCl(aq)

Which of the following combinations of chemicals could be used to make a buffer solution? Show

HCl/NH3

Which is a net ionic equation for the neutralization reaction of a weak acid with a weak base?

HF(aq) + NH3(aq) ⇌ NH4+(aq) + F-(aq)

Which is the best acid to use in the preparation of a buffer with pH = 3.3?

HNO2 (Ka = 4.5 × 10-4)

Which of the following titrations result in a basic solution at the equivalence point?

HOCl titrated with NaOH

What is the equilibrium constant expression for the Ksp of Ca3(PO4)2?

Ksp = [Ca2+]3[PO43-]2

Which is the best acid to use in the preparation of a buffer with pH = 9.3?

NH3 (Kb = 1.8 × 10-5)

Which pair of ions can be separated by the addition of sulfide ion?

Pb2+ and Ca2+

Which metal sulfides can be precipitated from a solution that is 0.01 M in Mn2+, Zn2+, Pb2+ and Cu2+ and 0.10 M in H2S at a pH of 0.50? -MnS = 3x10^10 -ZnS = 3x10-2 -Pb6 =3x10-7 -CuS 6x10-16

PbS, CuS

What is the most soluble salt of the following set?

Sn(OH)2 with Ksp = 1.6 × 10-19

Potassium chromate is slowly added to a solution containing 0.20 M AgNO3 and 0.20 M Ba(NO3)2. Describe what happens if the Ksp for Ag2CrO4 is and the Ksp of BaCrO4 is

The Ag2CrO4 precipitates first out of solution and then BaCrO4 precipitates.

Which metal sulfides can be precipitated from a solution that is 0.01 M in Mn2+, Zn2+, Pb2+ and Cu2+ and 0.10 M in H2S at a pH of 1.0? -MnS = 3x10^10 -ZnS = 3x10-2 -Pb6 =3x10-7 -CuS 6x10-16

ZnS, PbS, CuS

If the pKa of HCHO2 is 3.74 and the pH of an HCHO2/NaCHO2 solution is 3.89, which of the following is TRUE?

[HCHO2] < [NaCHO2]

If the pKa of HCHO2 is 3.74 and the pH of an HCHO2/NaCHO2 solution is 3.74, which of the following is TRUE?

[HCHO2] = [NaCHO2]

An important buffer in the blood is a mixture of

carbonic acid and bicarbonate ion.

When 50 mL of 0.10 M NH4Cl is added to 50 mL of 0.10 M NH3, relative to the pH of the 0.10 M NH3 solution the pH of the resulting solution will

decrease

Precipitation of an ionic compound will occur upon mixing of desired reagents if the initial ion product is

greater than the Ksp.

What is the Henderson-Hasselbalch equation for the acidic buffer HA/A-?

pH = pKa + log{[A-]/[HA]}

What is the pH at the equivalence point of a weak acid-strong base titration?

pH > 7

When titrating a strong monoprotic acid with KOH at 25°C, the

pH will be equal to 7 at the equivalence point.

When titrating a monoprotic strong acid with a weak base at 25°C, the

pH will be less than 7 at the equivalence point.

What is not a correct expression for the weak acid HA?

pKa = logKa