Principles of Chemistry I 3150: EXAM I Thursday, 5:10PM EXAM FOR PRACTICE USE FALL 2017

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1 Name Bubble on your scan sheet the Test Number and Test Form below: Principles of Chemistry I 3150: EXAM I Thursday, 5:10PM EXAM FOR PRACTICE USE FALL 2017 TEST 6, FORM A September 29, pts. Instructions: 1. Each student is responsible for following instructions. Read this page carefully. 2. Enter your name on this page and on your scan sheet. SIGN YOUR NAME on the scan sheet. Your signature on the scan sheet states your agreement with the following statement: I certify that I have not given or received aid on this exam, and that all work on the exam is entirely my own. 3. CODE your name (LAST NAME FIRST) on the computer answer sheet using an ordinary (No. 2) pencil. It is very important to code the information correctly!! Use your full name as it is in UA s records, not any nickname. 4. Put all calculations on the examination pages or scratch paper. Do not make any extra marks on the computer answer sheet!! 5. This exam consists of 33 multiple-choice questions worth 6 points each. For each multiple-choice question, choose the ONE best or correct answer and both write it on your exam paper and bubble it on the answer sheet. The computer answer sheet is the only one that will be graded! 6. Unless otherwise stated in a question: atoms and molecules are in the ground state; solutions are aqueous; and substances are at 25 C and 1 atm (~100 kpa). 7. This exam booklet consists of 7 pages (including this one), a Periodic Table/Formula Sheet, and a sheet of blank paper. Please check to be sure that you have them all! KEEP YOUR EXAM BOOKLET AND ANSWER SHEET COVERED TO PROTECT THE INTEGRITY OF YOUR WORK! PROHIBITED DURING EXAM: cell phones, pagers, laptops, PDAs, headphones, hats worn low over the eyes Please put these items away until you have left the room. REALLY, REALLY important information about bubbling your scan sheet: You MUST use a No. 2 pencil to bubble your answer sheet. Sheets completed in ink can not and WILL NOT BE GRADED. Enter your first and last names as far to the LEFT as possible in the fields. WRITE the letters of your name in the boxes at the top of the columns. (Dr. Donovan can not read bubbles.) In the STUDENT ID field, enter two zeros, then your 7-digit UA ID number. (if your ID number has fewer than 7 digits, fill with zeros so that your number is as far to the right as it can go.) That is, enter ID Number as You MUST bubble 3150: in the Dept/Course/Section fields. You MUST bubble the TEST NUMBER AND TEST FORM shown above. FAILING TO BUBBLE EVERYTHING CORRECTLY WILL PREVENT OR SIGNIFICANTLY DELAY PROCESSING OF YOUR EXAM!! If you erase and change an answer, please try using the white plastic eraser at the front of the room to remove the old mark. The scanner is VERY sensitive to erased marks! Thanks. The Management Warning!!! Doing any of the following will result in earning a score of zero (0) for this test. using INK to complete the bubble sheet not entering your name on the answer sheet not signing your name to the answer sheet not entering the TEST NUMBER and TEST FORM as noted above

2 What is the formula of ammonium sulfate? (A) AmSO 4 (B) Am 2 SO 4 (C) (NH 4 ) 2 SO 4 (D) NH 4 SO 4 (E) (NH 4 ) 2 S What is the formula of iron(iii) nitrate trihydrate? (A) Ir 3 NO 3 H 2 O (B) Ir(NO 3 ) 3 3H 2 O (C) Fe 3 NO 3 3H 2 O (D) Fe(NO 3 ) 3 3H 2 O (E) Fe(NO 2 ) 3 3H 2 O The formula for the ionic compound calcium pertechnate is Ca(TcO 4 ) 2. What is the formula for sodium pertechnate? (A) Na 3 TcO 4 (B) Na 2 TcO 4 (C) Na(TcO 4 ) 2 (D) Na(TcO 4 ) 3 (E) NaTcO 4 Which is a pair of isotopes? (A) 15 N and 15 O (B) 29 Si and 30 Si (C) 87 Sr 2+ and 87 Sr (D) 9 Be and 24 Mg (E) 12 Mg 2+ and 10 Ne Which calculation would give the total number of electrons in 41 g of Na atoms? (A) ( ) (B) ( ) (C) 41 ( ) (D) ( ) (E) ( ) Which shows a symbol for an anion of plutonium-238? (A) 238 Pt 2 (B) 238 Pt 2+ (C) 238 Pu + (D) 238 Pu 2 (E) 238 Pu 2 7. Which would most likely result in calculating a reaction percent yield that is over 100%? (A) random errors in the analytical balance. (B) splattering of the reactants as they are heated. (C) spilling some of the products on the benchtop before weighing. (D) weighing the product sample while wet. 3150: Exam I 2 9/29/16

3 Which contains 25 electrons? (A) 59 Co (B) 47 Ti 22 (C) 55 Mn (D) 25 Mg 12 What is the coefficient for O 2 when the equation is balanced with the smallest whole numbers? P 4 S 3 (s) + O 2 (g) SO 2 (g) + P 4 O 10 (l) (A) 1 (B) 13 2 (C) 8 (D) 13 (E) 15 When 10.0 g of H 2 reacts with 10.0 g of Cl 2, 6.97 g of HCl were recovered. What was the percent yield? H 2 (g) + Cl 2 (g) 2HCl(g) (A) 1.93% (B) 33.9% (C) 34.9% (D) 67.8% (E) 69.7% Which is symbolized by the diagram? 36e 39p + 50 (A) 39 Y 50 (B) Y 39 (C) Y 3 50n o 89 3 (D) 39 Y 89 (E) 36Kr A g sample of a compound containing only nitrogen and oxygen is analyzed and found to contain g N. What is the empirical formula of the compound? (A) NO (B) NO 2 (C) N 2 O 2 (D) N 2 O 4 (E) N 2 O 5 Molar Mass/g mol 1 H Cl HCl Naturally occurring boron contains two isotopes, 10 B and 11 B. The abundance of 10 B is (A) about 5%. (B) about 20%. (C) about 50%. (D) about 80%. (E) about 95%. 3150: Exam I 3 9/29/16

4 Which quantity contains the fewest atoms? (A) 2.0 g C 60 (B) 2.0 g H 2 (C) 2.0 g S 8 (D) 2.0 g O 3 (E) all contain the same number of atoms Which row in the table is INCORRECT? (A) (B) (C) (D) (E) protons neutrons electrons 39 K Mn Cd Ba Pb Calculate the percent by mass of oxygen in the mineral fluoroapatite, which has the formula Ca 5 (PO 4 ) 3 F. (A) 3.77% (B) 15.09% (C) 18.43% (D) 38.07% (E) 39.74% Which type(s) of chemical bonding involve attractive forces between positive and negative charges? (A) ionic bonding (B) covalent bonding (C) both (A) and (B) (D) neither (A) nor (B) Which combination of formula and name is incorrect? (A) NaNO 3, sodium nitrite (B) P 4 S 3, tetraphosphorus trisulfide (C) ZnCl 2, zinc chloride (D) (NH 4 ) 3 PO 4, ammonium phosphate An industrial chemical process is carried out in three steps with yields of 80.0%, 90.0%, and 74.0% respectively. What is the yield of the overall process? (A) 53.3% (B) 74.0% (C) 80.0% (D) 81.3% (E) 90.0% What element is a fourth-period alkaline earth metal? (A) K (B) Ca (C) Ti (D) Sr (E) Sn 3150: Exam I 4 9/29/16

5 21. How many grams of nitrogen gas can be formed when g N 2 H 4 and g N 2 O 4 react? 2N 2 H 4 (l) + N 2 O 4 (l) 3N 2 (g) + 4H 2 O(l) (A) 31.0 g (B) 131 g (C) 183 g (D) 331 g (E) 662 g liters of a solution contain 294 g of HClO 4. What is the molarity of the solution? (A) M (B) 1.46 M (C) 1.86 M (D) 2.69 M (E) 2.80 M A student prepares a solution by measuring 1.00 L of water, adding 0.50 mol of glucose, and mixing. What is the molarity of glucose in the solution? (A) 0.50 M (B) 1.0 M (C) 1.5 M (D) 2.0 M (E) it s impossible to tell without additional information. How many milliliters of 1.80 M CaCl 2 are needed to make ml of a 0.76 M solution? (A) 7.89 ml (B) 127 ml (C) 312 ml (D) 410 ml (E) 711 ml Which element does NOT commonly form ions with a 2+ charge in compounds? (A) Sr (B) Fe (C) Cu (D) Ag (E) Zn 26. This diagram represents a microscopic view of a gaseous (A) mixture of two elements. (B) mixture of two compounds. (C) mixture of an element and a compound. (D) element. (E) compound. 27. Which element exists in its most stable form as diatomic molecules? (A) helium (B) mercury (C) sulfur (D) fluorine (E) carbon Molar Mass/g mol 1 N N 2 H N 2 O Molar Mass/g mol 1. HClO : Exam I 5 9/29/16

6 Cortisol is one of the major steroid hormones used in the treatment of rheumatoid arthritis. Cortisol is 69.6% C, 8.34% H, and 22.1% O by mass. If the molar mass of cortisol is g mol 1, how many oxygen atoms are in the molecular formula for cortisol? (A) 1 (B) 5 (C) 10 (D) 15 (E) 21 Which quantity contains the LARGEST mass of cobalt? (A) g Co(s) (B) mol CoCl 3 (s) (C) mol Co(s) (D) mol Co 2 O 3 (s) (E) Co atoms Which is an empirical formula? (A) SO 3 (B) H 2 S 2 (C) both (A) and (B) (D) neither (A) nor (B) How many grams of CaCl 2 are needed to make 50.0 ml of a 3.0 M solution? (A) 7.55 g (B) 11.1 g Molar Mass/g mol 1 (C) 11.3 g CaCl (D) 16.6 g (E) 150 g A student titrated a mL sample of citric acid (H 3 C 6 H 5 O 7 ) solution with a M solution of sodium hydroxide. The titration required ml of sodium hydroxide solution. What was the concentration of the citric acid solution? H 3 C 6 H 5 O 7 (aq) + 3NaOH(aq) Na 3 C 6 H 5 O 7 (aq) + 3H 2 O(l) (A) M (B) M (C) M (D) M (E) M A student recorded the readings shown for the mass of a 25-gram weight whose mass is calibrated within g. The data are (A) accurate and precise. (B) accurate but imprecise. (C) inaccurate but precise. (D) inaccurate and imprecise. Data for mass of weight g g g g 3150: Exam I 6 9/29/16

7 1A (1) 1 H Li Na K Rb Cs Fr (223) 2A (2) 4 Be Mg Ca Sr Ba Ra [226] 3B (3) 21 Sc Y Lu Lr (262) 4B (4) 22 Ti Zr Hf Rf (267) Activity Series of Metals Li(s) Li + (aq) + e K(s) K + (aq) + e Ba(s) Ba 2+ (aq) + 2e Ca(s) Ca 2+ (aq) + 2e Na(s) Na + (aq) + e Mg(s) Mg 2+ (aq) + 2e Al(s) Al 3+ (aq) + 3e Mn(s) Mn 2+ (aq) + 2e Zn(s) Zn 2+ (aq) + 2e Cr(s) Cr 3+ (aq) + 3e Fe(s) Fe 2+ (aq) + 2e Co(s) Co 2+ (aq) + 2e Ni(s) Ni 2+ (aq) + 2e Sn(s) Sn 2+ (aq) + 2e Pb(s) Pb 2+ (aq) + 2e H 2 (g) 2H + (aq) + 2e Cu(s) Cu 2+ (aq) + 2e Ag(s) Ag + (aq) + e Hg(l) Hg 2+ (aq) + 2e Pt(s) Pt 2+ (aq) + 2e Au(s) Au 3+ (aq) + 3e 57 La Ac [227] 5B (5) 23 V Nb Ta Db (268) 58 Ce Th INCREASING ACTIVITY 6B (6) 24 Cr Mo W Sg (271) 59 Pr Pa B (7) (8) Mn Fe Tc (98) 75 Re Bh (270) 60 Nd U Ru Os Hs (269) 61 Pm (145) 93 Np [237] N A = B (9) (10) Co Ni Rh Ir Mt (278) 62 Sm Pu (244) 46 Pd Pt Ds (281) 63 Eu Am (243) 1B (11) 29 Cu Ag Au Rg (281) 64 Gd Cm (247) 2B (12) 30 Zn Cd Hg Cn (285) 65 Tb Bk (247) 3A (13) 5 B Al Ga In Tl Nh (286) 66 Dy Cf (251) 4A (14) 6 C Si Ge Sn Pb Fl (289) 67 Ho Es (252) 5A (15) 7 N P As Sb Bi Mc (289) 68 Er Fm (257) 6A (16) 8 O S Se Te Po (209) 116 Lv (293) 69 Tm Md (258) 7A (17) 9 F Cl Br I At (210) 117 Ts (294) 70 Yb No (259) 8A (18) 2 He Ne Ar Kr Xe Rn (222) 118 Og (294) Note: notation such as g mol 1 is read grams per mole. T K = T C T F = 9 5 T C + 32 T C = 5 9 [T F 32] E = q + w q = mc T w = P V H = E + P V H = n H F (products) n H F (reactants) M 1 V 1 = M 2 V 2 H = nd(bonds broken) nd(bonds formed) M = mol/l 1 1 cal = J specific heat of water = J g 1 K h = J s c = m s 1 R H = J 1 c = ν E = hν E RH 2 n PV = nrt D = P RT M 1 1 r r n A B P V T = P V 2 2 T 1 2 B M M 1 R = L atm mol 1 K 1 atm 760 torr = 760. mmhg = kpa = 14.7 psi = mbar P i = X i P T P T = P i P 1 /P T = n 1 /n T 1 in 2.54 cm (exact) actual % yield = 100% BO = 1 theoretical 2 [#bonding e #antibonding * e ] A