DO NOT OPEN THE EXAMINATION PAPER UNTIL YOU ARE TOLD BY THE SUPERVISOR TO BEGIN CHEMISTRY 2202 FINAL EXAMINATION. Value: 100% Time: 2 hours

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1 Name: Teacher: DO NOT OPEN THE EXAMINATION PAPER UNTIL YOU ARE TOLD BY THE SUPERVISOR TO BEGIN CHEMISTRY 2202 FINAL EXAMINATION Value: 100% Time: 2 hours General Instructions This examination consists of two parts. Both parts are contained in this booklet and further general instructions are provided on appropriate pages. Part I - Multiple Choice (40%) Select the letter of the correct response from those provided. EITHER shade the letter on your computer scorable card OR place the letter in the blank provided on your Multiple Choice Answer Sheet, whichever format is being used by your school for this exam. Do ALL questions in this section. Part II - Constructed Response (60%) Answer ALL questions fully and concisely in the space provided. Show all work, and use correct units and significant digits in all final answers. A Periodic Table and a Chemistry Data Sheet are provided. Student Checklist The items below are your responsibility. Please ensure that they are completed. Write your name and teacher's name on the top of this page. Write your name, teacher s name, course name and number on the Part I answer sheet. Check the exam to see that there are no missing pages. ALL MATERIALS MUST BE PASSED IN WITH THIS EXAM. Use your time wisely. Good luck!

2 1. How many neutrons are in phosphorus-32? Part I Total Value: 40% 2. How many molecules are in 1.75 mol of OF 2? 3.44 x x x x What is a mole? 12 g of carbon g of fluorine L of O 2(g) at 100 C x 10 atoms of H in H O 2 4. What is the molar mass of MgCO 3 5H2O? g/mol g/mol g/mol g/mol 5. Which has the greatest volume? 0.50 mol of helium gas at S.T.P. 2.0 L of ice at 0 C 6.0 L of oxygen at 25 C and atmospheric pressure 150 ml of water at room temperature 6. Which gas would have a mass of g and a volume of L at S.T.P.? Ar(g) He(g) Kr(g) Ne(g) 7. What is the percent composition of H in an organic compound containing only C, H and O if the percent composition of C and O are % and %, respectively? % % % % 8. What is the percent composition of hydrogen in ammonium chloride, NH4Cl? 1.89 % 2.00 % 7.55 % 8.00 % Chemistry 2202 Final Examination Page 1 of 13

3 9. What is the identity of "X" in the compound Na2X, given that the percent composition of sodium in the compound is 58.91%? Cl F O S 10. What is meant by the term aqueous when referring to a chemical substance? It is dissolved in water It is highly acidic It is in the liquid phase It is not very soluble in water 11. Which term has the same meaning as the chemistry term solution? heterogenous mixture homogeneous mixture immiscible mixture irreversible mixture 12. The solubility of KNO 3 at 25 C is 38g/100mL H2O. A beaker contains 76g of KNO3 dissolved completely in 200mL of water at 25 C. Which term describes the solution? dilute saturated supersaturated unsaturated 13. Which substance is considered to be an electrolyte? C6H6 CH3OH H2O KBr 14. What volume of 3.00 mol/l HCl(aq) would contain mol of hydrochloric acid? 0.167L 0.667L 1.50L 6.00L 15. What is the percent by volume of ethanol in a mixture of 175 ml of ethanol in ml of water? 30.0% 41.2% 58.8% 70.0% 16. According to the equation below, how many moles of oxygen will combine with 2.00 mol of phosphorus? P 4(g) + 5 O 2 (g) 2 P2O 5(s) 2.00 mol 2.50 mol 7.00 mol 10.0 mol Chemistry 2202 Final Examination Page 2 of 13

4 17. For the reaction below, how much A is required to form 5.00 g of B and 3.00 g of C? 2.00 g 8.00 g 15.0 g 16.0 g 2 A B + C 18. How is Plaster of Paris related to gypsum? Plaster of Paris can be made by dehydrating gypsum. Plaster of Paris decomposes over time into gypsum. Plaster of Paris forms when water is added to gypsum Plaster of Paris undergoes combustion to produce gypsum. 19. Which is an ionic compound? BrF CaS CF 4 NH Which type of intramolecular bonding involves sharing of electrons? covalent hydrogen ionic metallic 21. How many valence electrons are in a sulfur atom? How many lone pairs are found on a fluorine atom? What is the VSEPR shape of an atom of H2S? linear pyramidal tetrahedral V-shaped (bent) 24. Which contains one lone pair at the central atom? AlCl 3 CO 2 PBr 3 SF 2 Chemistry 2202 Final Examination Page 3 of 13

5 25. Which phrase best describes electronegativity? an atom's attraction for electrons an ion's ability to lose electrons two atoms sharing electrons in a bond two ions transferring electrons in a bond 26. For the molecule below, which element at position X would make a correct chemical structure for a polar molecule? F C I S 27. What is true of a V-shaped (bent) molecule? It is always polar if bond dipoles are present. It is never polar if bond dipoles are present. It is polar only when the two atoms bonded to the central atom are not the same. It is polar only when the two atoms bonded to the central atom are the same. 28 Which bond is the most polar? C-Cl C-F F-Cl F-F 29. Which is the best conductor of electricity? I 2(aq) I 2(s) NaCl(aq) NaCl(s) 30. Which substance would be expected to be a brittle solid at room temperature? Cl 2 H2O MgCl 2 SiO Why does ice float? The hydrogen bonds in ice cause ice to be less dense than water. The hydrogen bonds in liquid water cause the liquid to be less dense than ice. The London Dispersion force in ice causes ice to be less dense than water. The London Dispersion force in water causes water to be less dense than ice. 32. Which is an organic compound? CHCl 3 Cl 2 NaHCO 3 NH Cl 4 Chemistry 2202 Final Examination Page 4 of 13

6 33. Which molecule is 4-methyl-2-pentene? 34. Which chemical is an isomer of cyclopentane? cyclopentene cyclopentyne 1-pentene 1-pentyne 35. What is the IUPAC name of the compound below? ethanal ethanone propanal propanone 36. Which functional group is found in amines? Chemistry 2202 Final Examination Page 5 of 13

7 37. Which substance can undergo an acid elimination reaction? ethanal ethanoic acid ethanol ethyl ethanoate 38. Which is trans-2-butene? 39. Which substance reacts with methanol to produce the compound below? ethanoic acid ethanol propanoic acid propanol 40. Which reaction occurs when a condensation polymer forms from its monomers? addition elimination esterification substitution END OF PART I Chemistry 2202 Final Examination Page 6 of 13

8 Part II Constructed Response Total Value: 60% Answer ALL questions in the space provided. Show all workings and report all final answers with correct significant digits and units. Value 41. (a) A compound contains 82.63% carbon and 17.37% hydrogen by mass. 4 (i) Find the empirical formula of the compound. 2 (ii) Find the molecular formula of the compound if its molar mass is g/mol. Chemistry 2202 Final Examination Page 7 of 13

9 41. (continued) Value 3 (b) (i) Calculate the volume of 2.00 mol/l NaCl(aq) needed to make ml of mol/l NaCl(aq). 2 (ii) Briefly state the steps you would use to make the NaCl(aq) solution (above) in the lab. You may wish to refer to the lab equipment below in your response. NOTE: Not all of the apparatus would need to be used. (filter paper) (weighing dish) (balance) Chemistry 2202 Final Examination Page 8 of 13

10 Value 41. (continued) 4 (c) Zinc metal reacts with aluminum chloride to precipitate aluminum metal. 2 AlCl 3(aq) + 3 Zn(s) 3 ZnCl 2(aq) + 2 Al(s) (i) If excess AlCl 3(aq) reacts with 2.35g of Zn(s), calculate the theoretical yield of Al(s) expected, in grams. 2 (ii) If the experiment produced g of Al(s), calculate the percent yield for the reaction (d) Calculate the volume of chlorine which contains 1.20 x 10 molecules of Cl 2(g) at S.T.P. Chemistry 2202 Final Examination Page 9 of 13

11 Value 41. (continued) 3 (e) A 3.34 g sample of a hydrated compound, SrS2O 3 xh2o contains 2.30 g of SrS2O3. How many water molecules, x, are hydrated for each strontium ion? 4 (f) An unknown alkaline earth metal (Group IIA) "M" reacts with a solution of sodium fluoride, NaF(aq), in a single replacement reaction: M(s) + 2 NaF (aq) 2 Na(s) + MF 2(aq) When g of the metal "M" reacts, g of Na(s) precipitates. What is the identity of the metal "M"? Show all workings. Chemistry 2202 Final Examination Page 10 of 13

12 Value 42. (a) For the molecule, PF 3: 6 (i) Draw the electron dot diagram. (ii) Draw the VSEPR shape diagram. (iii) What is the name of the molecular shape? (iv) Is the molecule polar or nonpolar? 3 (b) The VSEPR shapes of three molecules are given below. (i) Under each shape, indicate with a yes (Y) or no (N) the type of intermolecular force present in each molecule. Molecule "A" Molecule "B" Molecule "C" London Dispersion Dipole-Dipole Hydrogen Bonding 3 (ii) Explain, using intermolecular forces, which molecule in (i) above has the highest boiling point. Chemistry 2202 Final Examination Page 11 of 13

13 Value 41. (continued) 3 (c) Three separate compounds have the formula C2H2F 2. Two are polar and one is nonpolar. Draw VSEPR structures for each of the compounds, and use molecular dipoles to show which compounds are polar. 2 (d) A student has two samples of white crystals in two separate containers. To the naked eye, the crystals appear to be identical. One of the crystals is sucrose (sugar), C12H22O 11(s), while the other is sodium chloride (table salt), NaCl(s). Other than simply tasting each substance, state TWO (2) different tests or measurements that the student can perform to determine which crystal is sugar and which is salt (a) Name each compound using IUPAC naming rules. (i) Name: _ (ii) Name: (iii) Name: Chemistry 2202 Final Examination Page 12 of 13

14 Value 43. (continued) 4 (b) Draw structural diagrams for the following: (i) 2-chlorobutanal (ii) 5-ethyl-2-heptyne 3 (c) For the reaction below: (i) identify the reaction type. (ii) complete and balance the reaction, and show structures for all organic molecules. Reaction Type: 3 (d) Two isomers (X and Y) have the formula C2H4O 2. Compound X can react to produce an ester. Compound Y is the organic product of an esterification reaction. Draw structural diagrams for compounds X and Y, and state the IUPAC name for each compound under its structure. Chemistry 2202 Final Examination Page 13 of 13