Problem 1
Which of the following schematic drawings best describes a solution of Li2SO4 in water (water molecules not shown for simplicity)?
Problem 2
Aqueous solutions of three different substances, AX, AY, and AZ, are represented by the three accompanying diagrams. Identify each substance as a strong electrolyte, a weak electrolyte, or a nonelectrolyte.
Problem 3
Use the molecular representations shown here to classify each compound as a nonelectrolyte, a weak electrolyte, or a strong electrolyte (see Figure 4.6 for the element color scheme). (a)
Problem 4
The concept of chemical equilibrium is very important. Which one of the following statements is the most correct way to think about equilibrium? (a) If a system is at equilibrium, nothing is happening. (b) If a system is at equilibrium, the rate of the forward reaction is equal to the rate of the back reaction. (c) If a system is at equilibrium, the product concentration is changing over time.
Problem 5
You are presented with a white solid and told that due to careless labeling it is not clear if the substance is barium chloride, lead chloride, or zinc chloride. When you transfer the solid to a beaker and add water, the solid dissolves to give a clear solution. Next an Na2SO41aq2 solution is added and a white precipitate forms. What is the identity of the unknown white solid?
Problem 6
Which of the following ions will always be a spectator ion in a precipitation reaction? (a) Cl- (b) NO3- (c) NH4+ (d) S2- (e) SO42-
- The labels have fallen off three bottles containing powdered samples of metals; one contains zinc, one contains lead, and the other contains platinum. You have three solutions at your disposal: 1 M sodium nitrate, 1 M nitric acid, and 1 M nickel nitrate. How could you use these solutions to determine the identities of each metal powder?
Problem 7
- In each of the following pairs, indicate which has the higher concentration of Cl- ion: (a) 0.10 M AlCl3 solution or a 0.25 M LiCl solution (b) 150 mL of a 0.05 M MnCl3 solution or 200 mL of 0.10 M KCl solution (c) a 2.8 M HCl solution or a solution made by dissolving 23.5 g of KCl in water to make 100 mL of solution.
Problem 7
- You want to analyze a silver nitrate solution. What mass of NaCl is needed to precipitate Ag+ ions from 45.0 mL of 0.2500 M AgNO3 solution?
Problem 8
Ch.4 - Reactions in Aqueous Solution