Chemistry 20 - Final Exam Review January 2015

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1 Name: Class: _ Date: _ Chemistry 20 - Final Exam Review January Oxygen and carbon dioxide are only slightly soluble in water because A. water is nonpolar B. they are made up of small molecules C. they are gases, not liquids D. they are made up of nonpolar molecules 2. During an investigation, a technician tested three samples of the same solution with three indicators. The results are shown in the following table. Indicator Colour bromocresol green blue chlorophenol red red phenolphthalein colourless The technician determined that the ph of the sample is: A. greater than 10.0 C. less than 3.8 B. between 5.2 and 6.8 D. between 6.8 and The limiting reagent of a chemical reaction is A. the reactant of a chemical process that is consumed completely B. the product of a chemical process that is consumed completely C. the product of a chemical process that is not consumed completely D. the reactant of a chemical process that is not consumed completely 4. Which of the following is not a strong acid? A. hydrofluoric acid C. sulfuric acid B. hydrochloric acid D. nitric acid 5. A solution whose precise concentration is known is called a A. standard solution C. concentrated solution B. dilute solution D. traditional solution 6. The mass of solute in 3.63 L of a 11.7 ppm solution is mg 7. Use the following information to answer this question. 1. sodium chloride 5. nitric acid 2. copper (II) sulfate 6. sodium nitrate 3. sodium hydroxide 7. sucrose 4. potassium dichromate 8 copper (II) nitrate A student is given four aqueous solutions. Each is prepared using one of the solutes listed above. A number of diagnostic tests are performed, and the results summarized below: Solution Red Litmus Blue Litmus ConductivColour silver nitrate added A red red high colorless no ppt B red blue high orange no ppt C red blue high blue ppt formed D red blue high blue no ppt Based on these test results, the identities of solutions A, B, C and D, respectively, are,,, 1

2 Name: 8. The substance that contains London forces, dipole-dipole forces, and hydrogen bonding between molecules is A. ammonia C. phosphorus trihydride B. methane D. hydrogen sulfide 9. Chloroacetic acid has the formula: CH 2 ClCOOH(aq). This acid is best be described as a A. a weak polyprotic acid C. a strong polyprotic acid B. a weak monoprotic acid D. a strong monoprotic acid 10. The oxygen atom has A. 6 bonding electrons, 2 lone pairs C. 2 bonding electrons, 2 lone pairs B. 4 bonding electrons, 4 lone pairs D. 8 bonding electrons, no lone pairs Scenario 8.1 Titration Analysis 1 A group of students performed a titration analysis. The results are given in the graph below. 11. Use Scenario 8.1 to answer the following question. The indicator that the students should use to find the endpoint ph is: A. methyl orange C. methyl red B. phenolphthalein D. bromothymol blue 2

3 Name: 12. According to its Arrhenius definition, a weak base A. completely dissociates to form OH + (aq) B. fully reacts with water to form OH + (aq) C. is an ionic hydroxide D. partially reacts with water to form OH + (aq) 13. In a particular reaction, the theoretical yield of the product is 2.84 g. If the actual yield is 1.92 g, what is the percent error? A % B. 32.4% C % D % 14. Which of the following reactions shows acetic acid, a common weak acid, reacting with water? < A. CH 3 COOH(aq) + H 2 O(l) "" 50% "! H 3 O + (aq) + CH 3 COO + (aq) B. CH 3 COOH(aq) + H 2 O(l) > "" 50% "! H 3 O + (aq) + CH 3 COO + (aq) C. CH 3 COOH(aq) + H 2 O(l)! H 3 O + (aq) + CH 3 COO + (aq) D. CH 3 COOH(aq) + H 2 O(l) > "" 99% "! H 3 O + (aq) + CH 3 COO + (aq) 15. Use the following information to answer this quesiton. Solution Litmus Conductivity 1 Blue to red high 2 no change none 3 Red to blue high 4 no change high The solution that can be classified as neutral ionic is A. 3 B. 1 C. 4 D An element X is found to have to following properties: 1. It forms ionic compounds 2. It forms negative ions when forming ionic bonds 3. It forms the compound MgX 2 when bonded to magnesium The element is most likely from A. Group 2 C. the alkali metals B. Group 16 D. the halogens 17. Which of the following is a polyprotic acid? A. CH 3 COOH(aq) C. HNO 3 (aq) B. H 2 CO 3 (aq) D. H 2 Cl(aq) 18. Pure oxygen boils at 183 C and freezes at 219 C. What state will the state of a sample of oxygen be if the sample s temperature is brought to within 50 K of absolute zero? A. gas B. solid C. plasma D. liquid 19. A volume of gas at 435 K and 1.75 atm is 31.7 L. The volume of gas at STP is L. 20. How much more acidic is vinegar (ph = 2.0) than coffee (ph = 5.0)? A. 3.0 B. 100 C. 2.5 D

4 Name: 21. If solutions of potassium chloride and silver nitrate are mixed, which of the following are spectator ions? A. K + and Cl + B. K + + and NO 3 C. Ag + + and NO 3 D. Ag + and Cl The mass of 2434 ml of ammonia gas at 96.5 C and 279 kpa is g. 23. For any confined ideal gas, when the temperature is increased and the volume is decreased at the same time, the A. pressure increases C. average kinetic energy decreases B. molecules move more slowly D. pressure stays constant 24. Determine the sum of all the reactant coefficients when the following equation is balanced: H 3 PO 4 (aq) + BaCO 3 (aq)! Ba 3 (PO 4 ) 2 (s) + H 2 O(l) + CO 2 (g) A. 9 B. 6 C. 5 D When the equation Ba(NO 3 ) 2 (aq) + Fe 2 (SO 4 ) 3 (aq)! BaSO 4 (s) + Fe(NO 3 ) 3 (aq) is correctly balanced, the coefficient of A. BaSO 4 is 4 C. Fe 2 (SO 4 ) 3 is 2 B. Ba(NO 3 ) 2 is 4 D. Ba(NO 3 ) 2 is The point during a titration at which a sharp colour change occurs is called the A. neutralization point C. mixed point B. endpoint D. fixed point 27. The volume of a given mass of a gas varies directly with the absolute temperature if the pressure is kept constant is a statement of A. Dalton s law C. Boyle s law B. Charles law D. Avogadro s law 28. A student dissolved 6.73 g of sodium carbonate to produce a mol/l solution. The solution s volume was ml. 29. According to the Lewis model of the atom, the number of bonding electrons in a nitrogen atom is A. 1 B. 2 C. 3 D Which piece of lab equipment is used for preparing a precise volume of a solution? A. graduated cylinder C. Erlenmeyer flask B. beaker D. volumetric flask 31. The hydronium concentration of a solution is 5.6 x 10-4 mol/l. The solutions s ph is. 32. Which of the following is not an electrolyte? A. an acid solution C. a basic solution B. salt dissolved in water D. sugar dissolved in water 33. The molecular shapes for carbon tetrachloride and hydrogen bromide are A. tetrahedral and V-shaped C. pyramidal and linear B. tetrahedral and linear D. linear and angular 4

5 Name: 34. Methane, CH 4 (g), and chloromethane, CH 3 Cl(l), differ in state at SATP mainly because A. methane is nonpolar and chloromethane has hydrogen bonding B. methane is nonpolar and chloromethane has dipole-dipole forces between molecules C. chloromethane and methane have the same tetrahedral shape and are nonpolar molecules D. chloromethane has a lower boiling point than methane 35. The molecule which is not isoelectronic with the others is A. C 2 Br C. BrCl B. C 4 H 10 Cl D. P 3 N 36. Cholesterol is a controversial substance found in the bodies of all people, and also found in many foods consumed by people. One property of cholesterol is that the molecule is non-polar. Because of this property, cholesterol must A. have a low solubility in water. C. be highly soluble in water. B. dissociate in water. D. be highly reactive in water. 37. In an experiment, 1.83 g of hydrogen at 94.1 kpa and 25.4 C is produced. What volume of hydrogen is expected? A L C L B L D L 38. The air pressure is the least in which of the following locations? A. Vancouver C. Jasper B. Edmonton D. The top of Mount Robson 39. What is the amount concentration of mol of potassium hydroxide dissolved in 0.68 L of solution? A mol/l C mol/l B. 2.4 mol/l D mol/l 40. Which of the following chemical equations is a correct dissociation equation? A. C 2 OH(l)! C 2 OH(aq) B. LiOH(s)! Li + (aq) + O 2 # (aq) + H + (aq) C. C 2 OH(l)! C 2 O # + H + (aq) D. NaCl(s)! Na + (aq) + Cl # (aq) 41. Fluorine gas is bubbled through a solution of sodium iodide. In this reaction, a spectator entity will be A. Na + (aq) C. I - (aq) B. F 2 (g) D. I 2 (s) 42. A student performs the World Famous Three Gram Lab one fine day. He prepares his two solutions and mixes them to react. He weighs his filter paper before filtration and records its mass as 0.60 g. After filtering and letting the precipitate dry over night, he weighs the filter paper and precipitate, and records their mass as 3.43 g. Based on his evidence, his percent error will be A. 5.7% C. 5.0% B. 14% D. 17% 5

6 Chemistry 20 - Final Exam Review January 2015 Answer Section 1. ANS: D 2. ANS: D 3. ANS: A 4. ANS: A 5. ANS: A 6. ANS: m = g = 42.5 g 7. ANS: 5, 4, 2, 8 8. ANS: A 9. ANS: B 10. ANS: C 11. ANS: D 12. ANS: D 13. ANS: B 14. ANS: A 15. ANS: C 16. ANS: D 17. ANS: B 18. ANS: B 19. ANS: v2 = L = 34.8 L 20. ANS: D 21. ANS: B 22. ANS: m = g = 3.77 g 23. ANS: A 24. ANS: C 25. ANS: D 26. ANS: B 27. ANS: B 28. ANS: ANS: C 30. ANS: D 31. ANS: ANS: D 33. ANS: B 34. ANS: B 35. ANS: B 36. ANS: A 37. ANS: A 38. ANS: D 39. ANS: D 40. ANS: D 41. ANS: A 42. ANS: A 1

7 Name: Class: _ Date: _ Version Review January 2015 Numeric Response 1. A student dissolves 1.2 g of sodim hydroxide to produce 4.36 L of solution. The ph of the resulting solution is. 2. The volume of a 2.44 ppm bromine solution which contains 97.9 µg of dissolved bromine is ml. 3. The ph of a solution where [H 3 O + (aq)] = 6.5! 10 "3 mol/l is. 4. The volume of air inside a 13.2 m x 4.42 m x 3.95 m building is seventy percent nitrogen, and thirty percent oxygen. If the air temperature is 26.8 C, and the pressure is kpa, then the total mass of air inside the building is kg. (Note: a volume of one m 3 = 1000 L) 5. A 10.6% W/V sodium nitrate solution contains 4.65 g of solute. The solution s volume is ml. 6. On the planet Zeepl, a fz volume of xefnid gas at a pressure of 3.95 bq is compressed to a new volume of 71.6 fz. The pressure of the compressed xefnid gas is bq. 7. The mass of solute present in 85.7 ml of a 38.3% W/V H2O2(aq) solution is g. 8. A 1.77 L volume of gas at SATP is compressed so that its volume is 908 ml. The pressure of the compressed gas is atm. 9. A student is given 1.69 L of a mmol/l solution of potassium carbonate. The mass of solute in the solution is mg. The solution s concentration can also be expressed as ppm. 10. The mass of 1262 ml of nitrogen gas at 95.4 C and 164 kpa is g. 11. The mass of mercury in 500 L of a 56.9 ppt solution is µg. 12. Joe s Bar introduces a new drink, with an alcohol concentration of 14.6 %V/V. One customer drinks seven 210 ml drinks. The customer consumed the equivalent of ml of pure ethanol. 13. If 7.75 g of hydrogen is used in the production of ammonia from its elements, then the mass of ammonia produced will be g. 14. A student burns 5.99 g of ethanol in 6.87 L of oxygen at 27.8 C and kpa. The mass of water vapour produced is g. 15. A solution is prepared by dissolving 4.65 g of calcium nitrate in 178 ml of water. The solution s amount concentration is mmol/l 16. The mass of barium nitrate hexahydrate required to produce 175 ml of 126 mmol/l solution is g. 17. A 20.6 ml volume of 125 mmol/l calcium chloride solution reacts exactly with a mol/l solution of silver nitrate. The volume of silver nitrate solution reacted is ml. 18. The poh of a solution is The [H 3 O + (aq)] = x 10 mol/l. 19. A student dilutes 22.1 ml of a 12.9 mmol/l sodium sulfate solution to a volume of 8.68 L. The concentration of the dilute solution is ppm. 1

8 Version Review January 2015 Answer Section NUMERIC RESPONSE 1. ANS: poh = ph = = ANS: v = ml = 40.1 ml 3. ANS: ph = = ANS: m (nitrogen) = kg m (oxygen) = kg m (total) = kg = 274 kg 5. ANS: v = ml = 43.9 ml 6. ANS: p2 = bq = 7.46 bq 7. ANS: m = g = 32.8 g 8. ANS: p2 = kpa p2 = atm = 1.92 atm 9. ANS: m = g = mg = 71.0 mg ppm = ppm = 42.0 ppm 10. ANS: m = g = 1.89 g 11. ANS: m = µg = 28.4 µg 12. ANS: v of ethanol = ml = 215 ml 13. ANS: mass of ammonia = g = 43.6 g 14. ANS: mass of water using ethanol = g mass of water using oxygen = g Limiting reagent: oxygen Answer: 5.02 g 15. ANS: amount concentration = mmol/l = 159 mmol/l 16. ANS: m = g = 8.15 g 17. ANS: v AgNO3 = ml = 40.2 ml 18. ANS: ph = [hydronium] = ! 10 "9 mol/l = 4.21! 10 "9 mol/l 19. ANS: mass of solute = g cf = ppm = 4.67 ppm 1