Solubility Written Response January 1999 3. In an experiment to determine the solubility of barium fluoride, 500.0mL of the saturated solution was heated in an evaporating dish to remove the water. The evaporating dish and residue were heated two more times, to ensure all the water had been driven off.

Using the data above, calculate the Ksp for BaF2 . (4 marks) April 1999 4. A 100.0mL sample of 0.600 M Ca(NO3)2 is diluted by adding 400.0mL of water. Calculate the concentration of ions in the resulting solution. (2 marks) 5. A maximum of 0.60g Pb(NO3)2 can be added to 1.5 L of NaBr(aq) without forming a precipitate. Calculate the [NaBr] (4 marks) June 1999 4. Write the net ionic equation representing the reaction that occurs when 50.0mL of 0.20M ZnSO4 and 50.0mL of 0.20M BaS are combined. (2 marks)

5. When 1.00g of MgCO3 is added to 2.0L of water, some, but not all, will dissolve to form a saturated solution. Calculate the mass of solid that remains undissolved. (4 marks) August 1999 4. The solubility of Mn(IO3)2 is 4.8 x 10-3

mol/L.

a) Write the net ionic equation that describes a saturated solution of Mn(IO3)2 . (1 mark)

b) Calculate the concentrations of the ions in a saturated solution of Mn(IO3)2 . (1 mark)

5. Consider the following saturated solutions at 25° C:

Using calculations, identify the solution with the greater [Ag ++] (5 marks) January 2000 5. a) Write the balanced formula equation for the reaction between Na3PO4(aq) and CuCl2(aq). (1mark)

b) Write the net ionic equation for the reaction between Na3PO4(aq) and CuCl2 (aq). (1 mark)

6. A saturated solution of nickel carbonate, NiCO3, contains 0.090g in 2.0L of solution. Calculate Ksp for NiCO3. (3 marks) April 2000 5. Calculate the maximum concentration of Pb+2

that can exist in 3.0 X10 –2 M Na2SO4

without forming a precipitate. (2 marks) 6. Consider the following:

a) Which two solid samples could be added to the CaS solution in order to remove first one ion and then the other from the solution. Indicate the order in which to add them. (2 marks) Firstadd:______________________Thenadd:______________________b) Write the net ionic equation for one of the precipitation reactions in part (a). (1 mark) June20004. At 20°C, will a precipitate form when 25.0mL of 0.010M Pb(NO3)2 is combined with 75.0mL of 0.010M NaI? Support your answer with calculations. (3 marks)

5. When HCl is added to a saturated solution of CuC2O4, some precipitate dissolves. However, when HCl is added to a saturated solution of PbCl2, additional precipitate forms.

Explain these observations. Support your explanation with chemical equations. (3 marks) August20004. a) Write the complete ionic equation for the reaction between NaBrO3 and AgNO3. (1 mark)

b) What is the maximum [NaBrO3] that can exist in equilibrium with 2.0M AgNO3? (2 marks) January20014. Write the balanced complete ionic equation for the reaction that occurs when 0.20M of Ba(NO3)2 is added to an equal volume of 0.20M Na2CO3. (2 marks)

5. Calculate the minimum number of moles of Pb(NO3)2 required to start precipitation in 50.0mL of 0.15M ZnI2. (5 marks)

April20014. In a titration, 25.00mL of NaCl(aq) ) reacts completely with 42.20mL of 0.100M AgNO3. What is the [Cl -] in the original solution? (3 marks) 5. The following data was obtained when 20.0mL of a saturated solution of PbI2 was evaporated to dryness.

Use this information to determine the Ksp of PbI2 . (4 marks) June20014. Calculate the molar solubility of SrF2. (4 marks) 5. Does a precipitate form when 3.0mL of 1.0 X 10-3 M NaBr is added to 2.0mL of 1.0 X 10-3

M Pb(NO3)2? (4 marks) August 2001 4. Hard water, containing Ca+2

ions, forms a precipitate with sodium stearate (NaC18H35O2). a) Write the net ionic reaction that represents this precipitation. (2 marks) b) Identify another compound that could be used to remove Ca+2

from hard water. (1 mark) 5. Calculate the mass of SrCO3 dissolved in 1.00L of a saturated solution of SrCO3. (3 marks)

January 2002 5) When equal volumes of 0.20 M Pb(NO3)2 and 0.20 M KCl are mixed, a precipitate of PbCl2 forms. a) Write the formula equation for the above reaction. b) Write the complete ionic equation for the above reaction. c) Write the net ionic equation for the above reaction 6) Calculate the maximum [CO3

2-] that can exist in 0.0010M Mg(NO3)2. April 2002 5) A 30.00mL sample of a saturated solution of Ag2SO4 was heated in an evaporating dish until all the water was evaporated. The following data were recorded:

Volume of solution 30.00mL

Mass of evaporating dish 32.125g

Mass of evaporating dish and solid Ag2SO4 32.260g

Calculate the Ksp value for Ag2SO4. June 2002 6) Calculate the solubility of SrSO4 in grams per litre.

August 2002 5) A 100.0mL saturated solution of FeF2 contains 0.0787g of solute. Determine [Fe2+] and [F-] in the solution. 6) Consider the following information and accompanying diagram: In a titration experiment, AgNO3(aq) was used to determine The [Cl-] in a water sample and the following data were recorded:

[AgNO3] = 0.125M Volume of water sample containing Cl- = 20.00mL

Initial buret reading of AgNO3 = 5.15mL Final buret reading of AgNO3 = 37.15mL

The equation for this reaction is Ag+

(aq) + Cl-(aq) → AgCl(s)

Using the above data, determine the [Cl-] in the water sample. January 2003 5) Calculate the mass of NaI necessary to begin precipitation of Cu+ from a 250.0mL ample of 0.010 M CuNO3. 6) When a solution of Na2CO3(aq) is mixed with a solution of Ca(NO3)2(aq) a precipitate forms. a) Write the net ionic equation for the precipitation reaction. b) Explain what happens to the precipitate when HCl is added.

April 2003 5) a) Write the net ionic equation for the reaction between Pb(NO3)2(aq) and NaCl(aq). b) Determine, with calculations, whether a precipitate will form when 15.0mL of 0.050M Pb(NO3)2 is added to 35.0mL of 0.085M NaCl. June 2003 5) After a 50.0mL sample of a saturated solution of Ag2SO4 was heated to dryness, 7.2 × 10-4 g of solid Ag2SO4 remained. What is the value of Ksp for Ag2SO4? August 2003 5) Calculate the maximum mass of BaCl2(s) that can be added to 250mL of 0.50M Pb(NO3)2(aq) without forming a precipitate of PbCl2(s).

Solubility Written Response Answers

January 1999 3)

April 1999 4)

5)

June 1999 4)

5)

August 1999 4a)

b)

5)

January 2000 5a)

b)

6)

April 2000 5)

6a)

b)

June 2000

4)

5)

August 2000

4a)

b)

January 2001

4)

5)

April 2001 4)

5)

June 2001

4)

5)

August 2001

4a)

4b)

5)

January 2002 5) a) Pb(NO3)2(aq) + 2KCl(aq) → PbCl2(s) + 2KNO3(aq) b) Pb2+

(aq) + 2NO3-(aq) + 2K+

(aq) + 2Cl-(aq) → PbCl2(s) + 2K+

(aq) + 2NO3-(aq)

c) Pb2+

(aq) + 2Cl-(aq) → PbCl2(s)

6) April 2002 5)

June 2002 6) August 2002 5) 6)

January 2003 5) 6) a) Ca2+

(aq) + CO32-

(aq) → CaCO3(s) b)

April 2003 5) a) Pb2+

(aq) + 2Cl-(aq) → PbCl2(s)

b) June 2003 5) August 2003 5)