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Chem 116 - General Chemistry II

Solubility and Common Ion

Solubility of Silver Phosphate in Water

What is the solubility (in units of g/L and g/100 mL) of silver phosphate (Ksp = 2.6×10-18) in water?

Video Solution

Solubility Product Constant

A saturated solution of Ce(IO3)3 has an iodate concentration of 0.0025 M. What is the numerical value of the solubility product constant?

Video Solution

Molar Solubility of Silver Sulfate

What is the molar solubility of silver sulfate (Ksp = 1.5×10-5) in:

A. pure water?
B. 0.50 M silver nitrate solution?
C. 0.30 M aluminum sulfate solution?

Video Solution

pH of Co(OH)3 Solution

What is the pH of an aqueous solution saturated with cobalt(III) hydroxide (Ksp = 1.1×10-15)?

Video Solution

pH and Molar Solubility of Mn(OH)2 Solution

An aqueous solution is saturated in manganese(II) hydroxide. What is the pH of this solution? What is the molar solubility of manganese(II) hydroxide (Ksp = 1.6×10-13) in an aqueous solution buffered at a pH of 8.00?

Video Solution

pH and Molar Solubility of Fe(OH)3 in Water

What is the pH of an aqueous solution saturated with iron(III) hydroxide (Ksp = 1.6×10-39)? What is the molar solubility of iron(III) hydroxide in pure water?

Video Solution

Solubility of Salts in Acidic Solutions

Consider the salts shown below. Which salts have increased solubility in more acidic solutions? Explain.

  • Mg(OH)2
  • Ag3PO4
  • PbBr2
  • MnS
  • CaSO3
  • Hg2I2


Video Solution

Precipitation

A solution is made by mixing 250. mL of 0.12 M AgNO3 with 100. mL of 0.0010 M Al2(SO4)3. Calculate the ion product. Will a precipitate form under these conditions? (for silver sulfate, Ksp = 1.5×10-5)

Video Solution

Solubility of Zinc Carbonate in Various Solutions

Consider the salt zinc carbonate (Ksp = 1.0×10-10) and the knowledge that zinc(II) forms the soluble ammonia complex ion Zn(NH3)42+ (Ksp = 7.8×108). Of the aqueous solutions, 0.20 M NH3, 0.30 M Na2CO3, pure water, and water with a pH buffered at 5.0, in which would the zinc carbonate be most soluble and in which the least soluble?

Video Solution

Selective Precipitation

A solution is 8.8×10-4 M in Th4+, Ca2+, and Li+. As NaF is slowly added to this solution, what [F-] is needed to precipitate as much of the Th4+ as possible without precipitating either the Li+ or the Ca2+?

Salt Ksp
ThF4 5.0x10-29
CaF2 3.2x10-11
LiF 1.7x10-3

What [F-] is needed to precipitate as much Th4+ and Ca2+ without precipitating the Li+?

At this [F-], what concentration of Th4+ and Ca2+ are left in solution and what percent of these ions have been precipitated?



Video Solution

Precipitation of Metal Bromides

A solution is 0.0050 M in bromide and is 4.0×10-3 M in Cu+, Pb2+, and Ag+. Under these conditions which metal cations will precipitate?

Salt Ksp
CuBr 5x10-9
PbBr2 6.6x10-6
AgBr 5.0x10-13

Video Solution

pH at Which a Precipitate Forms

A solution has an H2S concentration of 0.10 M and is 4.0×10-4 M in Co2+. At what pH will CoS first begin to precipitate from solution? (KspA (CoS) = 3)

Video Solution

Determining Molar Solubility

Aluminum(III) forms the soluble complex ion Al(OH)4- (Kf = 3×1033). What is the molar solubility of Al(OH)3 (Ksp = 3×10-34) in 2.0 M NaOH?

Video Solution

Identifying Precipitates

Aqueous solutions of AgNO3 and Na2CrO4 are mixed. Identify the precipitate (if any) that forms.

Video Solution

Molar Solubility

Calculate the molar solubility (in mol/L) of the following compounds in pure water.

 

BaCrO4 Ksp = 1.2 X10-10

 

Mg(OH)2 Ksp = 5.6 X10-12

 

Au(OH)3 Ksp = 3.0 X10-6

Video Solution

Ksp

Give the Ksp expression in terms of molar solubility, s, for Ca3(PO4)2 (s) in pure water.

Video Solution

Calculating Molar Solubility

Ca(OH)2 is only sparingly soluble with a solubility product of KSP is 6.5 X 10-6   

Calculate the molar solubility of Ca(OH)2 in pure water.
Calculate the molar solubility of Ca(OH)2 in 0.10 M Ca(NO3)2.   
Calculate the molar solubility of Ca(OH)2 in 0.10 M NaCl.

Video Solution

Calculating pH of a Saturated Solution

Calculate the the pH of a sat’d Mg(OH)2 solution.

KSP Mg(OH)2 = 5.6×10-12

Video Solution

Formation of a Precipitate

Does a precipitate form when 0.100 L of 0.30 M Ca(NO3)2 is mixed with 0.200 L of 0.060 M NaF? KSP of CaF2 = 3.2 X 10-11

Video Solution

Solubility

Write balanced equations to explain whether or not the addition of H3O+ from a strong acid affects the solubility of each of the following ionic compounds:

lead(II) bromide


copper(II) hydroxide


iron(II) sulfide



Video Solution

Calculating Molar Solubility

Calculate the molar solubility, s, of Mg(OH)2 in pure water. KSP of Mg(OH)2 = 5.6×10-12  

 

Calculate the molar solubility of Mg(OH)2 in water buffered at a pH of 13.00.

Video Solution

Precipitation

Describe what happens as potassium chromate, K2CrO4, is slowly added to a solution containing 0.20 M AgNO3 and 0.20 M Ba(NO3)2. 

 

KSP for Ag2CrO4 is 1.1×10–12 , KSP of BaCrO4 is 1.2×10–10.

Video Solution

Calculating KSP

A saturated solution of CuCl in water was prepared and filtered. From the filtrate, 1.0 L was measured out into a beaker and evaporated to dryness. The solid CuCl residue recovered in the beaker was found to weigh 0.041grams. Calculate the solubility product constant, Ksp, for CuCl.

Video Solution

Formation of a Precipitate

Will a precipitate form of BaCO3 on mixing equal volumes (200. ml) of the following solutions?        

 

Ksp (BaCO3) = 2.6×10-9 

 

3.0×10-3 M BaCl2 and 2.0×10-3 M Na2CO3  

 

1.0×10-5 M Ba(NO3)2 and 4.0×10-5 M Na2CO3

Video Solution

Calculating Molar Solubility

MgF2 is only sparingly soluble with a solubility product KSP = 7.4×10-11   

 

Calculate the molar solubility of MgF2 in 0.10 M NaF

 

Calculate the molar solubility in 0.10 M MgCl2

Video Solution

Selective Precipitation I

Consider a solution containing three metal cations;    [Pb2+] = [Ag+] = [Hg22+ ] = 0.0015M. 

At what concentration of Cl–(aq) will each salt just begin to precipitate (be at equilibrium)?

Ksp of PbCl2 = 1.7×10-5        Ksp of AgCl = 1.8×10-10      Ksp of Hg2Cl2 = 1.4×10-18   


What concentration of chloride ion must be present to precipitate as much of the Hg22+ (as Hg2Cl2) as possible without precipitating the chlorides of Ag+, and Pb2+?

Video Solution

Selective Precipitation II

Consider the solution of the previous problem containing three metal cations;

[Pb2+] = [Ag+] = [Hg22+ ] = 0.0015M.


We just determined that:


The PbCl2 system was at equilibrium when [Cl–] = 0.11 M,


The AgCl system was at equilibrium when [Cl–] = 1.2 X 10–7 M,


The Hg2Cl2 system was at equilibrium when [Cl–] = 3.1 X 10–8M.


Questions:
What concentration of Cl– ions is needed to precipitate all of the ions but Pb2+?


What is the concentration of Hg22+ ions in the solution at this concentration of Cl–?

Video Solution

Calculating Molar Solubility

Calculate the molar solubility of AgCl in pure water  given that the Ksp of AgCl = 1.8×10–10      

Ag+(aq) forms the complex Ag(NH3)2+(aq)  in a strong solution of ammonia. Calculate the molar solubility of AgCl in 3.0 M NH3     

Ksp of AgCl = 1.8×10–10           Kf of Ag(NH3)2+(aq) = 1.7×107

Video Solution

Calculating Molar Solubility

Calculate the equilibrium concentrations of Ag(CN)2–, I–(aq), and CN–(aq) if excess solid AgI is added to 1.00 M CN–(aq).      

 

Ksp of AgI = 8.3×10-17    and     Kf of Ag(CN)2– = 7.1×1019

Video Solution

Calculating Molar Solubility

Calculate the molar solubility of AgI in 0.500 M thiosulfate solution (S2O3-2).  

 

Ksp of AgI = 8.3×10-17  and   Kf of Ag(S2O3)2-3 = 1.70×1013 

Video Solution

Calculating Molar Solubility

Calculate the molar solubility of Cu(OH)2(s) in a solution of 1.2 M NH3.

 

Ksp of Cu(OH)2 = 1.6×10-19;      Kf of [Cu(NH3)4]2+ = 1.1×1013  

Video Solution