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5 Chem 201 Page 7 of 14 SECTION II: To be graded manually (Total value 42) Answers must be written in non-erasable ink to be considered for re-grading! Show all your work for full marks. QUESTION 15 VALUE 8 MARKS Structure A: Structure B: O O C C C C O C C C C a) Functional group in A: Functional group in B: b) Condensed formula: Condensed formula: c) Structure A (C 4 8 O) when mixed with MnO 4 undergoes an redox reaction to make the corresponding Structure B (C 4 8 O 2 ) and MnO 2. Complete the steps to draw out both the half reactions and the overall balanced redox reaction.

6 Chem 201 Page 8 of 14 d) If 0.2 moles of Structure A reacted with 0.4 moles of MnO 4, which would be the limiting reagent? e) If 0.05 moles of Structure B were formed when performing this reaction, what would be the percent yield for this reaction?

7 Chem 201 Page 9 of 14 QUESTION 16 VALUE 7 MARKS There are equivalent best resonance structures one can draw for 2 ClO 4. a) In Box A, the skeleton is given for one of the equivalent resonance structures. Complete the resonance structure in Box A by adding lone pairs and/or multiple bonds. b) In Box B draw an equivalent resonance structure to the species in Box A. Box A O Box B O Cl O O c) On the structure in Box A draw curved/curly arrows to show how electrons move between the two resonance structures. d) Draw out the resonance hybrid for this structure, assign all non-zero formal charges and indicate the bond order for all Cl O bonds within the structure.

Condensed formula Condensed formula b) Name the functional groups present. Functional group Functional group c) Give the IUPAC name.

8 Chem 201 Page 10 of 14 QUESTION 17 VALUE 8 MARKS The following questions refer to the line drawings the boxes below. Fill in the answers in the boxes provided a) Write the condensed formulae. Condensed formula Condensed formula b) Name the functional groups present. Functional group Functional group c) Give the IUPAC name. Name Name d) Draw the VSERP diagrams. VSEPR VSEPR e) The table below refers to atoms labelled 1-3 in the line diagrams above. Fill in the VSEPR details. Atom Electron-pair Molecular Bond Atom Geometry Shape Angles 1 3 Electron-pair Geometry Molecular Shape Bond Angles 2

9 Chem 201 Page 11 of 14 QUESTION 18 VALUE 6.5 MARKS a) In the box below redraw the above reaction using VSEPR diagrams for all four species participating in the reaction. b) In the box above use curly arrows to account for all the bonds that are being broken and bonds that are being formed. c) In the box above, circle the product of the reaction that contains an ionic bond. d) Rationalize why the hydrogen attached to oxygen as opposed to one of the hydrogens attached to carbon is removed preferentially in the acid base reaction above.

10 Chem 201 Page 12 of 14 QUESTION 19 VALUE 6 MARKS The resonance structures below belong to caffeine. 4 a) Fill in the curly arrows that would be required to interconvert resonance structure 1 to resonance structure 2 and resonance structure 2 to resonance structure 3. b) Follow the curly arrows in resonance structure 3 to draw the resonance structure 4 in the box provided c) On Caffeine, Structure 1, circle and name the two functional groups present.

11 Chem 201 Page 13 of 14 QUESTION 20 VALUE 6.5 MARKS Students in a previous year were asked a certain set of questions. The questions and the students answers are given in the table below. Complete the table by identifying which of the students responses are correct and which are incorrect. explaining your choices and drawing the correct response when needed. Question Student response incorrect or correct? Your explanation of why the answers are correct or incorrect and show what corrections need to made. Draw the VSEPR of C 2 F 2. F F C What is the shorthand/noble gas electron configuration of Fe 2+? [Ne] 4s 1 3d 5 In thinking about K + and S 2, which would have the larger ionic radius and why? K + would have a larger ionic radius because it has a lower electron affinity, meaning that the atom is more spread out. *******END OF WRITTEN ANSWER SECTION*******

15 Chem 201 Page 7 of 14 SECTION II: To be graded manually (Total value 36) Answers must be written in non-erasable ink to be considered for re-grading! QUESTION 13 VALUE 4 MARKS 13. With the boxes to the right, use one carefully worded sentence to explain what has happened to the contents of the flasks between before and after. Before: After: 210mL 90 ml Calculate how many moles are in the flask after the change: Before: After: 220mL 90mL Calculate how many moles are in the flask after the change:

16 Chem 201 Page 8 of 14 QUESTION 14 VALUE 5.5 MARKS 14. Canada contains 11% of the world s nickel (Ni) supply. a) What is the full spdf electron configuration of Ni in the ground state? The ionic compound NiCl2 is used in electroplating the surface of our 5 cent coins. b) What are the shorthand orbital box configurations for both the nickel cation and chloride anion? c) The anion is. ( paramagnetic / diamagnetic ) d) The size of a chlorine atom is than the size of the chloride anion due to (larger / smaller) the. (proton-electron ratio / distance valence e- are from the nucleus) Explain your reasoning.

Chem 201 Page 9 of 14 QUESTION 15 VALUE 8 MARKS When the electrons in a collection of excited hydrogen atoms relax, some of them change their wave-function from Orbital A to Orbital B (shown to the

Orbital A is a orbital Orbital B is a orbital 15. b) What is a possible set of quantum numbers for each of these orbitals? Orbital A: Orbital B: 15.

17 Chem 201 Page 9 of 14 QUESTION 15 VALUE 8 MARKS When the electrons in a collection of excited hydrogen atoms relax, some of them change their wave-function from Orbital A to Orbital B (shown to the right): Orbital A Orbital B 15. a) Name the orbitals. Make sure to indicate the orientation of the orbital by making reference to the axes, when necessary. Orbital A is a orbital Orbital B is a orbital 15. b) What is a possible set of quantum numbers for each of these orbitals? Orbital A: Orbital B: 15. c) What do the representations for orbitals A and B, given above, convey about electron probability? 15. d) There are four other orbitals that are degenerate with Orbital A. Name these orbitals and draw their Boundary diagrams by completing the table below. Make sure to include axes in both the names and diagrams. Boundary Diagram Orbital 1 Orbital 2 Orbital 3 Orbital 4 Name 3dxz 3dyz

18 Chem 201 Page 10 of 14 QUESTION 16 VALUE 4 MARKS 16. a) There are two equivalent resonance structures one can draw where the octet rule is satisfied for all the atoms of SO2. Complete the skeleton in Box A that shows one of them and then draw its equivalent Lewis Structure in Box B. Box A Box B 16. b) Are these structures the best Lewis structures possible for SO2? Explain your reasoning behind why or why not? If you believe they are not the best, draw the best Lewis structure as part of your answer.

19 Chem 201 Page 11 of 14 QUESTION 17 VALUE 8 MARKS 17. a) Draw a Lewis structure for the molecular formula C44O that contains the functional groups aldehyde and alkyne. Lewis structure 17. b) What is the condensed formula for this compound? 17. c) Draw the Lewis for a possible constitutional isomer of the molecule in 16. a) that contains a ketone and alkyne. Lewis structure 17. d) What is the condensed formula for this compound?

20 Chem 201 Page 12 of e) Complete the following table for the species PBr3 : Lewis VSEPR structure Electronpair geometry is Molecular shape is Tetrahedral Trigonal pyramidal Bond angles are <109.5

21 Chem 201 Page 13 of 14 QUESTION 18 VALUE 6.5 MARKS 18. L-Dopamine is found to help patients with Parkinson s disease but it is unable to pass the bloodbrain barrier. It s precursor L-Dopa, however, can (shown below). L Dopa a) Write what functional group(s) is/are present in L-Dopa in the box below. Carboxylic acid, amine, alcohol, alkene or benzene c) L-Dopa when mixed with NaO reacts as follows: b) On the structure of L-Dopa choose a functional group where there are significant polar bonds and draw the partial charges (δ +, δ ) on the it. simplified structure of L Dopa Draw curved arrows to show how bonds are made and broken between reactants to for the products. d) The product circled above can be drawn in two ways (A & B shown to the right). Draw curved arrows on both these structures to show how electron movement will lead to their inter-conversion. A B e) A and B are known as. f) Their inter-conversion is known as. g) In the box between A and B draw the arrow that is used to indicate that they can be interconverted. *******END OF WRITTEN ANSWER SECTION*******

COURSE: CHEMISTRY 211, Foundations of Chemistry: Structure and Bonding

DEPARTMENT OF CHEMISTRY COURSE SYLLABUS FALL 2014 COURSE: CHEMISTRY 211, Foundations of Chemistry: Structure and Bonding LEC DAYS TIME ROOM INSTRUCTOR OFFICE PHONE EMAIL L01 TR 11:00-12:15 EEEL161 Dr.