NAME _____________________________________ Student No. ___________________________ SECTION (circle one): A01 (Codding) A02 (Sirk) A03 (Briggs) UNIVERSITY OF VICTORIA Version A CHEMISTRY 101 Mid-Term Test 1, October 15, 2010 Version A This test has two parts: PART I is a multiple choice section and is worth 26 marks. The answers for the 14 questions in this part must be coded on the optical sense form using a SOFT PENCIL. PART II consists of written answers and is worth 24 marks. Answer these questions on this examination paper. Answers written partially or completely in pencil cannot be re-marked. Hand in this entire test paper AND your optical sense form (bubble sheet) at the end of the examination period (60 minutes). The basic Sharp EL510 calculator is the only one approved for use in Chemistry 101. A Data Sheet accompanies this test. Marks for Written Answers Question 1 [6] Question 2 [4] Question 3 [3] Question 4 [2] Question 5 [4] Question 6 [3] Question 7 [2] TOTAL (/24) Multiple Choice (/26) Raw Written Score (/24) Raw Score /50 TOTAL MARK (%) Chemistry 101, Mid-Term Test 1 Version A Page 2 of 8 PART I – Multiple Choice: Select the BEST response for each question below. [Total marks = 26] 1. This is exam Version A. Mark “A” as the answer to question 1 on the optical sense form. 2. 3. An electron having n = 3 and ml = +1 A. must have ms = +½ B. must have l = 1 C. may have l = 1 or 2 D. must have l = 2 E. must be in a p orbital An atomic orbital represents: A. the shape of an atom. B. the repulsion of all the electrons among themselves. C. a fixed path that an electron follows around the nucleus of an atom. D. the region of high probability for an electron around the nucleus of an atom. E. the region of electron density for a covalent bond. 4. In a hydrogen atom, orbitals with the same energy: I) II) III) IV) V) 5. extend about the same distance from the nucleus. have the same principal quantum number, n. are referred to as isoelectronic. are referred to as degenerate. are represented by 1s and 2s orbitals A. I, III, IV B. I, IV, V C. I, II, IV D. I, II, III E. I, II, III, and IV Which of the following statements about orbitals is CORRECT? A. The average distance from the nucleus of a 3s electron in a chlorine atom is smaller than that for a 3p electron on the same atom. B. There is no experimental evidence that an electron behaves as if it has spin. C. The 2s orbitals have a node at the nucleus. D. The five 3d orbitals are alike except for the orientation with respect to the axes. E. The quantum number l denotes the orientation of an orbital with respect to the other orbitals. 6. What is the energy (in J) of one mole of photons with the energy of the 434 nm line in the hydrogen spectrum? 5 A. 2.76 × 10 -19 D. 4.58 × 10 -4 B. 9.21 × 10 E. 1.73 x 10-7 -4 C. 2.80 × 10 Chemistry 101, Mid-Term Test 1 7. Page 3 of 8 Element M is directly below element X in the periodic table. Which of the following statements is/are CORRECT? i) ii) iii) iv) A) B) C) D) E) 8. Version A M has a greater ionization energy than X. M has a larger bonding atomic radius than X. M and X have the same number of core electrons. The cation X+ is smaller than the cation M+. i, ii and iv i and ii i and iii ii and iii ii and iv Which of the following is a violation of the Pauli Exclusion Principle? 9. The electron configuration for the ground state of ruthenium 3+ ion (Ru3+) is: A) [Kr]5s1 4d4 B) [Kr]4d6 C) [Kr]4d5 D) [Kr]5s2 4d3 E) [Ar]4d5 10. Which of the following statements is INCORRECT? A. B. C. D. E. Anions (negative ions) are larger than the parent atoms from which they are formed. Atomic radius decreases from left to right across a row in the periodic table. In an isoelectronic series, the species with the largest number of protons has the largest radius. The halogens (Group VIIA, 17) have the most negative electron affinities. The first ionization energy of Mg is greater than the first ionization energy of Ba. Chemistry 101, Mid-Term Test 1 Version A Page 4 of 8 11. Consider the three ionic compounds LiF , KI, KF. Which response is CORRECT for the increasing order of lattice energy (i.e. smallest to largest)? A. B. C. D. E. KI < KF < LiF LiF < KF < KI KF < KI < LiF LiF < KI < KF KF < LiF < KI 12. Consider a Lewis structure of POCl3 that follows the octet rule for all atoms. (Note; P is bonded directly to each of the three Cl and to the O atom.) Which statement below is CORRECT? A. B. C. D. E. Each Cl has 5 valence electrons. The molecule has 18 lone pairs of electrons (i.e. non-bonding pairs). The molecule has a total of 30 valence-shell electrons. The Lewis structure has four single bonds. The Lewis structure has one double bond and three single bonds. 13. Of the molecules LiF, HF, HCl, H2O and KCl, the covalently bonded compounds are: A) B) C) D) E) KCl and H2O HF and KCl LiF and KCl LiF and HF HF, HCl and H2O 14. If A > B means that element A is more electronegative than element B, which of the following is INCORRECT? A) B) C) D) E) Al < P S < Te O<F Ge < P Cs < Na Chemistry 101, Mid-Term Test 1 Version A Page 5 of 8 Part II written answers to questions: Write your answers directly on this test paper. Show all your work. Hand in the entire test paper at the end of the test period. [Total marks = 24] 6 marks 1.[3]a) Draw the energy level diagram for the first 4 energy levels in the hydrogen atom in the space below. Label the diagram with values for n and indicate the direction of increasing energy. [1] b) Assume that the electron in the hydrogen atom has been excited to the n = 2 level. Starting from that excited state, indicate with an arrow labeled “E” on the diagram in part (a) a transition that corresponds to the hydrogen atom emitting radiation, and indicate with an arrow labeled “A” a transition that corresponds to the hydrogen atom absorbing radiation. [2] c) Which of the two transitions labeled in (b) would involve the largest change in energy? Calculate the energy required for that transition. Chemistry 101, Mid-Term Test 1 Version A Page 6 of 8 4 marks 2. On the basis of the periodic table and the basic rules of building electron configurations, indicate the following: [1] a) the ground state electron configuration for Sb [1] b) the maximum number of unpaired electrons that can occupy the 4f subshell ___________________ [1] c) the maximum number of electrons that can have n = 2 and ms = - ½ _________________________ [1] d) the four quantum numbers of the LAST electron to be placed into a Ca atom ____________________ 3 marks 3. Draw one example of each of an s, p and d orbital on the axes below. Be sure to label your drawings with s, p or d, as appropriate. Chemistry 101, Mid-Term Test 1 Version A Page 7 of 8 2 marks 4. Based on trends in the periodic table, arrange the bonds in each of the following sets in increasing order of bond polarity (i.e. smallest to largest polarity). Note: the format X—Y < W—T means the polarity of bond X—Y is less than the polarity of bond W—T. (a) C—F, O—F, B—F (b) O—Cl, Be—Cl, C—Cl 4 marks 5. Draw ONE valid Lewis structure that obeys the octet rule for the ion [CNO]. (The atoms are connected in the order written.) Show all bonding pairs of electrons as lines, all non-bonding valence electrons as dots, and calculate all formal charges and show all non-zero formal charges. Chemistry 101, Mid-Term Test 1 Version A Page 8 of 8 3 marks 6. (a). Write the chemical equation, indicating the states of all reactants and products, corresponding to the second ionization energy (I2) of calcium (Ca). (b). Why is the third ionization energy of calcium (I3) so much greater than the second ionization energy? 2 marks 7. Is the effective nuclear charge (Zeff) experienced by an outer shell electron of fluorine (F) greater than or less than that of an outer shell electron of carbon (C)? Explain briefly. ++++++++++++++++++++++++++++ THE END +++++++++++++++++++++++++++++++++