Sch3u Test Review With Answers 3h3a1v

SCH3U: Unit 4 Review Solutions Vocabulary : Please do not waste your time memorizing . Just make sure that you generally know what they mean in case they come up in a question. Solution Homogenous Solute Solvent Solubility Miscibility Aqueous solution Concentration Dilution

Acid Base Strong vs. Weak Acid Electrolyte Ionization Dissociation pH Titration

Key Concepts : What is a solution? Describe the difference between a solute and a solvent Molar concentration (mol/L) Preparing an aqueous solution by dissolving (solid into liquid) Preparing an aqueous solution by dilution (C1V1 = C2V2) Reactions in aqueous solution (when will single and double displacements happen?!) Solution stoichiometry (finding the limiting and excess reagent, and predicting yield) What are acids and bases? The pH scale and calculating pH Titration (using results & stoichiometry to calculate an unknown concentration)

Practice questions : 1. Identify a solvent and a solute in each solution below. a) salt water b) brass (Cu + Zn) d) coffee with sugar e) acid rain

c) chocolate milk f) air

2. A student dissolved 5.00g of sodium carbonate in water to produce an aqueous solution with a total volume of 250 mL. Determine the molar concentration of the solution. [0.19 mol/L] 3. A lab technician must prepare 3.00L of 0.125 mol/L sodium hydroxide solution. What mass of sodium hydroxide should he use to prepare the solution? [15.0 g] 4. You are asked to prepare 2.00L of cobalt (II) chloride with a concentration of 0.250 mol/L for an experiment. Calculate the mass of cobalt (II) chloride required, and explain step-by-step how to prepare the solution. [64.9 g] 5. You are asked to prepare 200mL of 0.010 mol/L hydrochloric acid (HCl). All you have available is 0.36 mol/L hydrochloric acid. What volume of 0.36 mol/L acid will you need to mix with water? [5.6 mL] 6. A student added some water to 0.20L of 2.40 mol/L NH3(aq) to reach a final volume of 1.00L. What is the new molar concentration of the solution? [0.48 mol/L]

7. Predict the products of each reaction then balance the equation. If there would not be a reaction, make sure to write “no reaction”. a)

KCl(aq) + Na(s)

b)

HCl(aq) + CuCl2(aq)

c)

BaBr2(aq)

+

F2(aq)

d)

Na2S(aq)

+

Pb(NO3)2(aq)

e)

Li2SO4(aq)

+



AgNO3(aq)





f)

K2CO3(aq)

+

CaCl2(aq)

g)

NiCl2(aq)

+

Cu(s)

h) CuSO4(aq)

+

KCl(aq)

i)

K3PO4(aq)

+

AlCl3(aq)

j)

ZnCl2(aq)

+

K(s)









8. A teacher wants to demonstrate the reaction between iron (III) chloride and sodium carbonate. If she plans to use 75.0 mL of iron (III) chloride with a concentration of 0.200 mol/L, what volume of 0.250 mol/L sodium carbonate should she use to have a perfect reaction with no limiting or excess reagent? [90.0 mL] 9. Ammonium sulfate ((NH4)2SO4) is used in fertilizer. It is manufactured in the synthesis reaction between sulfuric acid (H2SO4) and ammonia (NH3). The synthesis uses 50.0 mL sulfuric acid to react completely (no excess reagent) with 24.4mL of 2.20 mol/L ammonia. What molar concentration of sulfuric acid was used in the synthesis? [0.537 mol/L] 10. A student mixed 400.0 mL of 0.0250 mol/L calcium hydroxide with 25.0 mL of 0.125 mol/L aluminum sulfate. What mass of aluminum hydroxide would be produced? (Don’t forget to find the limiting reagent first.) [0.49g] 11. In a reaction between 15.0 g of calcium hydroxide and 75.0 mL of 0.500 mol/L HCl, what mass of water would be produced? (Don’t forget to find the limiting reagent first.) [0.675 g] 12. You have analyzed the properties of 4 solutions : Ca(OH)2, HCl, sugar (C12H22O11), and salt (NaCl). Your results are shown in the table below. Identify solutions A, B, C, D. Table 1 : Properties of solutions A Neutral electrolyte B Acid electrolyte C Neutral Non-electrolyte D Base electrolyte [ANSWERS : A – NaCl, B – HCl, C – sugar, D – Na(OH)2]

13. A sample of liquid soap has a hydrogen ion [H+] concentration of 1,0 x 10-10 mol/L. What is its pH? [10] 14. A sample of acid rain contains 0.00oo45 mol/L of hydronium ions. What is the pH of the rain ? [4.3] 15. Determine the pH of each solution :

a) 0.035 mol/L HCl [1.5] c) 0.001 mol/L NaOH [11]

b) 0.0068 mol/L H2SO4 d) 0.045 mol/L Ca(OH)2

[1.9] [13]

16. In a titration you used vous 23.85 mL of 0.150 mol/L caclium hydroxide to neutralize exactly 50.0 mL of chloric acid. What was the concentration of the chloric acid? [0.143 mol/L] 17. An antacid tablet contains 0.912g of aluminium hydroxide. What volume of stomach acid (0.10 mol/L HCl) can one antacid tablet neutralize? [351 mL]