St. Charles College Final Exam 12U Chemistry Teacher: Mrs. D. Johnston Time: 2 hours Marks: 108

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1 St. Charles College Final Exam 12U Chemistry Teacher: Mrs. D. Johnston Time: 2 hours Marks: 108 Instructions: 1: Please answer Part A on the answer sheet, Part B in the space provided and Part C on foolscap and graph paper. 2: Answer all of Part A and all of Part B. For Part C, answer only 4 questions of your choice 3: Use the proper problem solving format when completing problems that involve calculations including significant digits. 4: The only resources allowed are a calculator and the resource booklet provided. 5: At the end of the exam, arrange pages in the following order: Answer sheet, Part B foolscap, exam questions, reference booklet. DO NOT STAPLE PAGES. WRITE YOUR NAME ON EVERY PAGE TO BE EVALUATED. Part A: Knowledge and Understanding (50 marks) Multiple Choice (30) 1. Which organic compound is unsaturated? a. ethylcyclopentane b. 2-methyl-3-ethylpentyne c. 1,1-dimethylhexane d. cyclohexane e. 1,3,5-trimethyloctane 2. Which feature do all aromatic hydrocarbons have? a. an amine group b. halogens c. a benzene ring structure d. an aldehyde group e. all double bonds in a ring 3. Which two compounds react to form an ester? a. a carboxylic acid and an alcohol b. an alcohol and an aldehyde c. an alcohol and a ketone d. a carboxylic acid and a ketone e. an aldehyde and a carboxylic acid 4. What type of reaction is most common for benzene to undergo? a. substitution b. hydrolysis c. oxidation d. reduction e. addition 5. What forms when water reacts with an alkene? a. an ester b. an acid c. an alcohol d. an amine e. a ketone 6. Which compound is formed by the oxidation of a secondary alcohol? a. tertiary alcohol b. aldehyde c. carboxylic acid d. primary alcohol e. ketone 7. Which object(s) would you use to describe the shape of the 2p orbital? Page of 10

2 s a full 3s orbita8l?. 12 U Chemistry NAME: Jan a. a dumb-bell b. a circle c. a sphere d. two perpendicular dumb-bells e. a doughnut a. B b. Na c. Mg d. Be e. Ne 9. How does atomic radius change from left to right across a period in the periodic table? a. It increases. b. It decreases. c. It stays the same. d. It increases and then decreases. e. It decreases and then increases. 10. What is the bond angle in a bent molecule, such as water? a. 90 b c d e What is the shape of a molecule of carbon tetrachloride, CCl 4? a. linear b. trigonal planar c. trigonal pyramidal d. tetrahedral e. angular 12. Which compound has polar covalent bonds? a. AgCl 2 b. CH 4 c. Cl 2 d. CF 4 e. B H Which process produces the most energy? a. cooking b. chemical reaction c. physical change d. dissolution e. nuclear reaction 14. In an exothermic reaction, H rxn is... a. always positive b. always negative c. negative or positive d. zero e. not possible to measure 15. Which statement does not describe an endothermic reaction? a. The surroundings cool down. b. H rxn is positive. c. Heat is released by the system. d. Heat is absorbed by the system. e. The potential energy of the products is greater than the potential energy of the reactants. 16. Which statement about the instantaneous rate of a reaction is not correct? a. The higher the rate, the greater is the slope of a line on a concentration-time graph. b. The instantaneous rate is the slope of the tangent to a line on a concentration-time graph. c. The instantaneous rate is the slope of the secant to a line on a concentration-time graph. d. The instantaneous rate decreases over time. e. All of these statements are correct. 17. Which factor will not affect the rate of the following reaction? Na AgNO NaNO Ag (s) 3(aq) 3(aq) (s) Page of 210

3 a. the addition of a catalyst b. an increase in pressure c. an increase in the concentration of AgNO 3(aq) d. an increase in temperature e. all of these factors will have a strong effect on the rate of the reaction Page of 310

4 18. Which step of a reaction is the rate-determining step? a. the fastest step b. the first step c. the last step of the reaction mechanism d. the step with the greatest number of molecules e. the slowest step 19. Which of the following affects the value of the equilibrium constant? a. temperature b. small changes in concentration c. the density of a slightly soluble salt d. small changes in the pressure of a gas e. adding a catalyst 20. What is the correct equilibrium constant for the following reaction? 2NO (g) 2H 2(g) N 2(g) 2H2 O(g) a. b. c. d. e. 21. What will happen to the following equilibrium if the pressure increases while the volume remains constant? 2IBr (g) I 2(g) Br2(g) a. The concentration of IBr will increase. b. The concentration of I 2 will increase. c. The concentration of Br 2 will decrease. d. There will be no change to the equilibrium system. e. The pressure will decrease. 22. Which statement does not describe a characteristic of acidic solutions? a. They react with metals to form hydrogen gas. b. They turn phenolphthalein pink. c. They do not react with fatty acids. d. They are made from non-metal oxides. e. They conduct electricity. 23. What is the formula of a hydronium ion? a. H3 O + (aq) b. OH (aq) c. H + (aq) d. H2 O + (aq) e. H O Which compound is a strong acid? a. HClO (aq) b. HIO 3(aq) c. HClO 4(aq) d. HC2H3O2(aq) e. NaOH 25. Which compound is NOT a strong base? a. Al(OH) 3 b. KOH c. Ba(OH) 2 d. NaOH e. Ca(OH) 2 Page of 410

5 26. Arsenic acid, H3AsO 4 (aq), reacts with water as follows: + H3AsO 4 (aq) + H2 O (l) H2AsO 4 (aq) + H3 O (aq) The conjugate base of H3AsO4 (aq) in this reaction is : a. H3AsO 4 (aq) b. H2 O (l) ch. 3 H 3 O + (aq) d. OH (aq) e. H AsO (aq) 27. If the [H+] in a solution is 1 x 10 4 mol/l, the ph is: a b. 1 c. 4 d e How many electrons need to be added to balance the following half-reaction? Br2(g) 2Br (aq) a. one electron to the right side b. one electron to the left side c. two electrons to the left side d. two electrons to the right side e. no electrons are needed for this equation 29. How would you assign the oxidation numbers of the elements in Co(ClO 3) 2? a. First, give the metal a charge of 1. Then divide the other atoms equally. b. Give oxygen an oxidation number of 2. Use this number to calculate the charge of chlorine, and then the charge of cobalt. c. Split this ionic compound into its two ions. The charge on the metal becomes its oxidation number. Assign oxygen an oxidation number of 2, and calculate the oxidation number of chlorine accordingly. d. The chlorate ion has a charge of 2. Calculate the oxidation numbers of chlorine and cobalt after you give oxygen its usual oxidation number. e. Since this is an ionic compound, the metal will have an oxidation number of zero. 30. Using the Redox Equation, KMnO 4 + HCl KCl + MnCl 2 + Cl 2 + H2O Which reactant is the oxidizing agent? a. K + b. KMnO 4 c. HCl d. Cl e. Cl2 Nomenclature (10) Page of 510

6 1. Write the IUPAC name on the answer sheet a) b) c) d) e) 2. Draw the structural diagram for each compound on the answer sheet a) methanamine b) 2-octanol c) propyl propanoate d) 4-ethyl-3,3-dimethyl-2-heptanone e) meta-dichlorobenzene Matching (10) NAME DEFINITION 1. Markovnikov a) the enthalpy change of a physical or chemical process is independent of the pathway of the reaction 2. Pauli b) temperature scale that begins at absolute zero 3. Faraday c) symbolic representation of the electrons of an element or compound 4. Hess d) a maximum of 2 electrons of opposite spin can occupy an orbital 5. Arrhenius e) a dynamic equilibrium tends to respond so as to relieve the effect of any change in the conditions that affect the equilibrium 6. Le Chatelier f) in an addition reaction of 2 asymmetrical reactants, the halogen or OH is usually added to the more substituted carbon atom 7. Hund g) defines an acid as a proton donor 8. Br nsted-lowry h) the amount of substance consumed or produced in an electrolysis reactions is directly proportional to the quantity of electricity that flows through the circuit 9. Kelvin i) defines an acid as a substance which produces hydrogen ions in water 10. Lewis j) the lowest energy state for an atom has the maximum number of unpaired electrons in a given energy sublevel Page of 610

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8 Part B: Short Answer Inquiry (27 marks) 1. Draw the Lewis structure for SO 2. How many bonded pairs of electrons and how many lone pairs of electrons are around the sulfur atom (2marks) 2. Identify the types of organic reactions. (5marks) a) b) c) d) e) o o 3a) When 600 ml of water in an electric kettle is heated from 20 C to 85 C to make a cup of tea, how much heat flows into the water? (4marks) b) The fuel that is used for space shuttles is a mixture of hydrazine, N2H 4(l), and dinitrogen tetraoxide, N2O 4(l). When these compounds are mixed, they react instantaneously and produce enough energy to get a shuttle to the Moon. The balanced chemical equation is given below. 2N2H 4(l) NO 2 4(g) 3N 2(g) 4H2 O(g) Using standard enthalpies of formation, calculate the heat of reaction for this fuel. (3marks) Page of 810

9 4a) The reactant concentration of a first-order reaction is 0.05 mol/l, and the rate constant is s. What is the rate of this reaction? (3marks) 2 1 b) The rate constant for the following reaction is s. What is the half-life of the reaction? CH CHO CH CO (3marks) 3 (g) 4(g) (g) 5. List three different strategies that could be used to shift the following equilibrium toward the reactants. Note: List changing concentration only once. (3marks) 2SO 197 kj 2SO O 3(g) 2(g) 2(g) 6. Identify the oxidizing agent and the reducing agent in the following redox reaction. Explain your answers. MnO 4 + SO Mn + SO 4 (4marks) Page of 910

10 PART C MAKING CONNECTIONS (28 marks) Do 4 of the following questions. Only the first 4 indicated on your foolscap will be marked. Answer each question on a separate page and in numerical order.. Each question is worth 7 marks. 1. The labels have fallen off three bottles. Bottle A contains a gas, bottle B contains a liquid, and bottle C contains a solid. The labels indicate that the compounds have the same number of carbon atoms, one being an alkene, one an amine, and the other an ether. Suggest the identity of the contents of each bottle, and give reasons for your answer. (7) ml of mol/l of copper(ii)sulfate (CuSO 4) solution is mixed with 50.0 ml of 1.00 mol/l solution of sodium hydroxide (NaOH) in a coffee-cup calorimeter. The temperature change is recorded to be 5.32 C. a) What is the enthalpy change for the reaction? (5) b) Write the thermochemical equation. (2) 3. The following data were obtained for the decomposition of dinitrogen pentoxide (N2O 5) in carbon tetrachloride (CCl ) solution at 45 C. 4 N2O 5 (mol/l) Time (min) a) Plot a graph of concentration of dinitrogen pentoxide versus time. (graph paper on next page) (3) b) Determine the instantaneous rate at 20 min and at 180 min. Account for the difference. (4) 4. Suppose that mol of A and mol of B are placed a 1.50 L container and the following hypothetical equilibrium is established. If the equilibrium amount of C is mol, what is the equilibrium constant for this reaction? (7) A 2B 3C (g) (g) (g) 5. For each of the following molecules, a) draw the three-dimensional representation and name the shape. (3) b) describe the intermolecular forces between the molecules (3) c) state which one would be more soluble in water and why (1) i) CCl4 ii) XeF4 iii) NF 3 6a) Write the half-reactions and calculate the standard cell potential for the following reaction. Identify whether the reaction is spontaneous or non-spontaneous and justify your answer. (2) Cr + AlCl CrCl + Al (s) 3 (aq) 3 (aq) (s) b) Calculate the mass of magnesium that can be plated onto the cathode by the electrolysis of molten magnesium chloride, using a current of 3.65 A for 55.0 min. (Faraday constant = C/mol) (5) Page of1100

11 ANSWER SHEET PART A MULTIPLE CHOICE /30 St. Charles College Final Exam 12U Chemistry NOMENCLATURE /10 1a) b) c) d) e) 2a) b) c) d) e) MATCHING / MARKS PART A /50 PART B /27 PART C /28 TOTAL /105 Page of1110

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Chapter 1 Reactions of Organic Compounds. Reactions Involving Hydrocarbons

Chapter 1 Reactions of Organic Compounds Reactions Involving Hydrocarbons Reactions of Alkanes Single bonds (C-C) are strong and very hard to break, therefore these compounds are relatively unreactive