Principles of Chemistry II CHEM 1212 Chapter 14
1. A reaction has the experimental rate equation Rate = k[A]2. How will the rate change if the concentration of A is tripled? If the concentration of A is halved?
2. Data for the reaction 2NO(g) + O2(g) → 2NO2(g) are given (for a particular temperature) in the table.
Experiment / [NO] / [O2] / Initial Rate (mol NO/L∙h)1 / 3.6 x 10-4 / 5.2 x 10-3 / 3.4 x 10-8
2 / 3.6 x 10-4 / 1.04 x 10-2 / 6.8 x 10-8
3 / 1.8 x 10-4 / 1.04 x 10-2 / 1.7 x 10-8
4 / 1.8 x 10-4 / 5.2 x 10-3 / ?
(a) What is the rate law for the reaction?
(b) What is the rate constant for the reaction?
(c) What is the initial rate of the reaction in experiment 4?
Rate= 0.0182 M-1h-1[NO][O2]
Rate= 1.7 x 10-8 M/h
3. The equilibrium constant, Kc, for the following reaction is 1.05 at 350 K.
2CH2Cl2(g) ↔ CH4(g) + CCl4(g)
If an equilibrium mixture of the three gases at 350 K contains 0.0206 M CH2Cl2(g) and 0.0163 M CH4(g), what is the equilibrium concentration of CCl4?
0.0273M
4. At 20 oC, a saturated aqueous solution of silver acetate, AgCH3CO2, contains 1.0 g of the silver compound dissolved in 100.0 mL of solution. Calculate Ksp for the silver acetate.
AgCH3CO2(s) ↔ Ag+(aq) + CH3CO2-(aq)
3.59x10-3
5. Calcium hydroxide, Ca(OH)2, dissolves in water to the extent of 1.78 g per liter. What is the value of Ksp for calcium hydroxide?
5.54x10-5
6. When 250 mg of SrF2, strontium fluoride, is added to 1.00 L of water, the salt dissolves to a very small extent. At equilibrium, the concentration of Sr2+ is found to be 1.03 x 10-3 M. What is the value of Ksp for SrF2?
4.37x10-9
7. The solubility of silver phosphate (Ag3PO4) is 4.4 x 10-5 M, Calculate the solubility product constant.
1.0x10-16
8. Estimate the solubility of the following in (a) moles per liter and (b) grams per liter of pure water (use Ksp values in appendix).
(i) lead(II)sulfate, Ksp=2.58x10-8; s=1.58x10-4M; 0.0479 g
(ii) HgS, Ksp=2.0x10-32; s=1.4x10-16 M; 3.26x10-14 g
(iii) AgBr, Ksp=5.4x10-13; s=7.3x10-7 M; 1.37x10-4 g
(iv) MgF2, Ksp= 5.2x10-11; s= 2.4x10-4 M; 0.0146 g
(v) PbI2, Ksp= 9.8x10-9; s=1.3x10-3 M; 0.599 g
9. The Ksp value of radium sulfate, RaSO4, is 4.2 x 10-11. If 25 mg of radium sulfate is placed in 1.00 x 102 mL of water, does all of it dissolve? If not, how much dissolves?
Q>K, 2.087 mg
10. Calculate the solubility of silver bromide, AgBr, in moles per liter, in pure water. Compare this value with the molar solubility of AgBr in 225 mL of water to which 0.15 g of NaBr has been added.
Without NaBr: 7.3x10-7 M; With NaBr: 3.7x10-10 M (à common ion effect!)
11. What is the solubility, in milligrams per milliliter, of BaF2, (a) in pure water and (b) in water containing 5.0 mg/mL KF?
Pure water: 3.6x10-3 M; With KF: 2.09x10-6 M