Pre-Test
1. The molarity of Cl- available in 110.0 mL of a solution containing 5.55 g of CaCl2 is:
2. How many grams of solute are contained in 141 mL of a 0.175 M silver nitrate solution?
3. Zn reacts with HCl to produce ZnCl2 and H2. What volume of 0.470 M HCl is required to produce 1.50 grams of ZnCl2? (molar mass of ZnCl2 = 136 g/mole.)
4. The net ionic equation for the reaction between calcium nitrate and sodium sulfate is:
5. Iron (II) sulfate reacts with concentrated potassium hydroxide in aqueous solution to form a precipitate. The net ionic equation for this reaction is
6. Which of the following salts is insoluble in water?
a) Na2S b) K3PO4 c) Pb(NO3)2 d) CaCl2 e) All are soluble in water.
7. How many of the following salts are expected to be insoluble in water?
sodium sulfide, barium nitrate, ammonium sulfate, potassium phosphate
a) none b) 1 c) 2 d) 3 e) 4
8. Which of the following ions is most likely to form an insoluble sulfate?
a) K+ b) Li+ c) Ca+2 d) S-2 e) Cl-
9. If all of the chloride within a 5.000-g sample of an unknown metal chloride is precipitated as AgCl with 70.90 mL of 0.2010 M AgNO3, what is the percentage of chloride in the sample?
10. 50.0 mL of 0.10 M silver nitrate is added to 50.0 mL of 0.20 M calcium chloride. A white precipitate forms. After the reaction is complete, calculate the amount of precipitate that formed.
11. A sample of Mg(OH)2 is allowed to stand with water for a long time, until the solution contains as much dissolved Mg(OH)2as possible. A 100.0mL sample of this solution is removed and titrated with 0.005000 M HBr. It requireds 48.8 mL of the acid to neutralize the base. What is the concentration of the Mg(OH)2 ?
12. A solid sample of Zn(OH)2 is added to 0.400 dm3 of 0.500 M solution of HBr. The solution that remains is still acidic. It is then titrated with 0.500M NaOH solution and 165.0mL of the NaOH solution is required to reach the equivilance point. What was the mass of the Zn(OH)2 added to the HBr solution?
13. Describe how to prepare 250.0mL of 0.500M barium hydroxide.
14. balance the following redox reaction
Cr2O7-2 + C2H5OH --> Cr+3 + CO2 + H2O (acidic)
15.. balance the following redox reaction
Cr + CrO4-2---> Cr(OH)3 (Basic)
Choose 5 of the following equations and write the net ionic reaction
A) solutions of sodium iodide and lead nitrate are mixed.
B) a solution of ammonia is added to a solution of ferric chloride
C) a solution of hydrogen peroxide is heated
D) solutions of silver nitrate and sodium chromate are mixed
E) hydrogen sulfide gas is bubbled through a solution of potassium hydroxide
F) solid dinitrogen pentoxide is added to water.
G) a piece of solid bismuth is heated strongly in oxygen
H) a strip of copper metal is added to a concentrated solution of sulfuric acid
Answers:
1)0.90M
2) 4.19g
3) 47mL
4) Ca+2 + SO4-2 --> CaSO4
5) Fe+2+ OH- ---> Fe(OH)4-2
6) E, 7) A, 8) C,
9)0.506 g Cl = 10.1%
10) 0.72g
11) 0.00122M
12) 5.84 g
13) Place 21.4 g of barium hydroxide into enough water to make 250.0mL of solution