SOLUTIONS PRACTICE TEST

1. Define solution.

2. If salt is dissolved in water, water serves as the _____.

3. If the addition of a crystal to an aqueous solution causes a great deal of dissolved solid to come out of solution, the original solution was _____.

4. A concentrated solution is one in which there is a (small or large) amount of solute in a (small or large) amount of solvent.

5. In general, as the temperature of a solvent increases, the solubility of any gas dissolved _____.

6. Increasing the temperature of a salt solution will generally increase the _____ of solute that dissolves and

_____ the rate at which a solute dissolves.

7. Write the balanced equation for dissolving each of the following salts.

a) K2S (s) b) Zn(NO3)2 (s) c) LiCl (s) d) Na3PO4 (s)

8. Sugar is soluble in water because sugar molecules are (polar or nonpolar).

9. Write the double replacement reaction for each of the following. You do not need to balance, but you may need to criss-cross the oxidation numbers of the newly formed products.

a) KOH and NH4Cl b) Na2SO4 and KCl

10. Identify the precipitate and the spectator ions in each of the following equations. In addition write the balanced, net ionic equation for each.

a) NaOH + CuCl2 → Cu(OH)2 + NaCl

b) NH4Cl + AgNO3 → AgCl + NH4NO3

Show your work (equation, substitution and answer with the correct unit) for #15-24.

15. What is the molarity of a 5.00 liter solution that was made with 10.0 moles ofKBr?

16. What mass in grams of Na2SO4 is needed to make 2.5 L of 2.0 M solution?

17. How many liters of a 2.00 M NaBr solution are needed to make 200. mL of 0.500 M NaBr?

18. To 225 mL of a 0.800 M solution of KI, a student adds enough water to make 1000. mL of a more dilute KI solution. What is the molarity of the new solution?

19. What mass in grams of sucrose, C12H22O11, is needed to make 500. mL of a 0.400 M solution?

20. How many moles of hydrochloric acid are contained in 1.45 L of a 2.25 M solution?

21. Calculate the molarity of the solution produced when 122 g of potassium carbonate (K2CO3) are added to water so the final volume is 1.20 L.

22. How many liters of solution are needed when 3.95 moles of lithium acetate (LiC2H3O2) form a 1.55 M solution?

23. A 250 ml solution is made with 0.50 moles of NaCl. What is the molarity of the solution?

24) 250. mL of a 5.00 M solution of HCl is diluted with water to form a 3.75 M solution. What is the final volume of the solution AND how much water should be added?

25. A solution is a mixture

a) from which the solute cannot be filtered.

b) that is colloidal.

c) that is heterogeneous.

d) in which a solid solute is always dissolved in a liquid solvent.

26. The rule like dissolves like is used to predict

a) solubility b) equilibrium c) reactivity d) phase

27. Which of the following is NOT a colligate property?

a) vapor pressure lowering b) boiling point elevation

c) freezing point depression d) melting point elevation

28. When solutions of two ionic compounds are combined and a solid forms, the process is called

a) hydration b) precipitation c) solvation d) dissociation

29. Which ions do NOT appear in the net ionic equation (spectator ions) for the precipitation reaction involving solutions of Zn(NO3)2 and Na3PO4 because they are ions in a soluble compound?

a) Zn+2 (aq) and NO3-1 (aq) b) Na+1 (aq) and Zn+2 (aq)

c) Zn+2 (aq) and PO4-3 (aq) d) Na+1 (aq) and NO3-1 (aq)

30. What happens to the solubility of a gas, in a liquid, if the external pressure above the liquid decreases?

a) The solubility decreases. b) The solubility increases.

c) The solubility remains the same.

31. A dilute solution is one in which there is a

a) small amount of solute in a large amount of solvent b) large amount of solute

c) small amount of solute in a small amount of solvent d) large amount of solvent

ANSWERS

15) 2.00 M 16) 711 g 17) 0.0500 L 18) 0.180 M

19) 68.4 g 20) 3.26 mol 21) 0.736 M 22) 2.55 L

23) 2.00 M 24) 0.333 L = final volume; 0.083 L of water must be added

Solutions Practice Test - page XXX