1 Exam I CHEM 1303.001 Name (print legibly) Seat no. On my honor, I have neither given nor received unauthorized aid on this exam. Signed Date Part 1. Nomenclature. 10 pts. total. 2 pts. each. Fill in the names and formulas in the table below. Name Formula KMnO 4 HBrO 2 aluminum iodide diiodine tetroxide nickel(ii) nitrate pentahydrate Part 2. Multiple choice (use answer card). 90 pts. total. 3 pts. each. Indicate the BEST answer for the questions in this section by completely filling in the appropriate space on the answer card with a #2 pencil. Mark only one space per question. 1. After carrying out the operations below, how many significant figures are appropriate to show in the result? (13.7 + 0.027) 8.221 a. 1 b. 2 c. 3 d. 4 e. 5 2. Which of the following is a physical change? a. Formation of rust. b. Dynamite explodes. c. Meat rots if it is not refrigerated. d. A silver platter tarnishes. e. Water evaporates.
3. The scientist who determined the ratio of the electric charge to the mass on the electron is a. Thomson. b. Dalton. c. Rutherford. d. Millikan. e. Curie. 2 4. 40.0 milligrams (mg) is how many megagrams (Mg)? a. 4.00 x 10 8 b. 4.00 x 10 2 c. 4.00 x 10 4 d. 4.00 x 10 5 e. 2.50 x 10 7 5. The density of ethanol, commonly know as grain alcohol, is 0.798 g/ml. Calculate the mass (in g) of 20.0 ml of the liquid. a. 0.0399 b. 16.0 c. 25.1 d. 20.8 e. 19.2 6. Liquid nitrogen boils at a temperature of 196 C. This temperature in kelvin is: a. 469 b. 77 c. 77 d. 469 e. 321 7. A cube measures 4.0 x 10 4 furlongs on each side. Calculate the volume of this cube in cm 3. 1 furlong = 2.0 x 10 4 cm. (A furlong is a distance unit used in horse racing. ) a. 2.00 b. 0.500 c. 8.00 d. 512 e. 1.95 x 10 3
8. From the list below, which is the most metallic. a. Mg b. Ba c. Co d. F e. C 3 9. The elements in Group 8A are known as the a. transition metals b. halogens c. noble gases d. alkaline-earth metals e. alkali metals 10. All formulas of ionic compounds are empirical formulas because a. ionic compounds are made up of different types of molecules. b. ionic compounds ionize. c. ionic compounds are composed of individual neutral atoms. d. ionic compounds are soluble in water. e. ionic compounds do not contain molecules. 11. An atom of 140 57 La contains a. 140 protons, 57 neutrons, and 140 electrons. b. 57 protons, 140 neutrons, and 57 electrons. c. 57 protons, 83 neutrons, and 83 electrons. d. 57 protons, 83 neutrons, and 57 electrons. e. 57 protons, 140 neutrons, and 57 electrons. 12. The total number of electrons in the ion N 3 is a. 10 b. 3 c. 7 d. 17 e. 24
13. Of the following compounds, which should be covalent (molecular)? a. CaS b. KH c. SCl 2 d. Zn 3 N 2 e. NaF 4 14. The empirical formula of a compound is found to be CH 2. If the molar mass of this compound is 70.0, its molecular formula is a. CH 2 b. C 2 H 4 c. C 4 H 22 d. C 4 H 8 e. C 5 H 10 15. All of the following elements exist as diatomic molecules except a. F 2 b. Cl 2 c. N 2 d. O 2 e. C 2 16. If you obtain a yield of 35.0 g in a reaction where you calculated the yield to be 65.0 g, what is your percent yield for this reaction? a. 35.0 b. 50.0 c. 53.8 d. 22.8 e. 100 17. Naturally occurring bromine occurs as two different isotopes in an almost 50:50 abundance. The atomic mass of bromine on the periodic table is 79.90. The most likely atomic masses of these two isotopes are a. 80 and 81 b. 79 and 80 c. 79 and 81 d. 81 and 82 e. 78 and 79
5 18. The number of atoms in 3.0 moles of Si is a. 93.0 b. 2.0 x 10 23 c. 5.0 x 10 24 d. 6.0 x 10 23 e. 1.8 x 10 24 19. The number of moles of As 4 S 4 that contains the same number of sulfur atoms as 10.0 moles of As 2 S 5 is a. 10.0 b. 2.00 c. 5.00 d. 20.0 e. 12.5 20. Which of the following has the most O atoms? a. 1.0 mole of Mn 2 (SO 4 ) 3 b. 3.0 moles of SO 3 c. 4.0 moles of SO 2 d. 5.0 moles of Na 2 O e. 2.0 moles of N 2 O 4 21. Consider the following unbalanced equation: a. 1 b. 2 c. 3 d. 4 e. 5 As 2 I 4 AsI 3 + As If the coefficient of As in the balanced equation is 2, the coefficient of AsI 3 must be
22. A compound contains 43.6% by mass P and 56.4% by mass O. Determine the empirical formula of this compound. 6 a. P 2 O 5 b. P 4 O 6 c. PO 4 d. PO e. P 3 O 8 23. Xenon difluoride reacts with water according to the following balanced equation: 2XeF 2 + 2H 2 O 2Xe + 4HF + O 2 If 0.50 moles of XeF 2 reacts completely with water, how many moles of HF will be formed? a. 0.25 b. 0.50 c. 1.0 d. 2.0 e. 4.0 24. Which two of the following elements would you expect to show the most similar chemical properties? P As Ne K O Br a. Br and O b. P and As c. Ne and P d. K and O e. As and O 25. Consider the following reaction in aqueous solution between Na 2 S and ZnCl 2 in aqueous solution. The correct net ionic equation for this reaction is a. Na 2 S(aq) + ZnCl 2 (aq) 2NaCl(aq) + ZnS(s) b. 2Na + (aq) + S 2 (aq) + Zn 2+ (aq) + 2Cl (aq) 2Na + (aq) + 2Cl (aq) + ZnS(s) c. 2Na + (aq) + S 2 (aq) + Zn 2+ (aq) + 2Cl (aq) 2Na + (aq) + 2Cl (aq) + Zn 2+ (aq) + S 2 (aq) d. S 2 (aq) + Zn 2+ (aq) ZnS(s) e. Na 2 S(aq) + ZnCl 2 (aq) ZnS(s)
26. Consider the following balanced equation (with molar masses given below each formula): PCl 5 + 4 H 2 O H 3 PO 4 + 5 HCl molar masses: 208 18.0 98.0 36.5 7 If 41.6 g of PCl 5 are mixed with 21.6 g of H 2 O, how many grams of HCl should be formed? a. 36.5 b. 7.30 c. 54.8 d. 43.8 e. 9.13 27. In the previous problem, how many grams of the excess reagent remain unreacted? a. 7.2 b. 14.4 c. 20.0 d. 5.4 e. 18.0 28. All of the following are strong electrolytes except a. CuCl 2 b. KCl c. LiClO 4 d. CH 3 COOH e. NaOH
29. All of the following are strong acids except a. HCl b. HF c. HClO 4 d. HNO 3 e. H 2 SO 4 8 30. How many moles of Ba(OH) 2 is needed to completely neutralize 0.60 moles of H 3 PO 4? a. 0.40 b. 1.2 c. 0.30 d. 0.90 e. 0.20
9 1A 8A (1) (18) 1 2 1 H 2A 3A 4A 5A 6A 7A He 1.008 (2) (13) (14) (15) (16) (17) 4.003 3 4 5 6 7 8 9 10 2 Li Be B C N O F Ne 6.941 9.012 10.81 12.01 14.01 16.00 19.00 20.18 11 12 13 14 15 16 17 18 3 Na Mg 3B 4B 5B 6B 7B.....8B. 1B 2B Al Si P S Cl Ar 22.99 24.31 (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) 26.98 28.09 30.97 32.07 35.45 39.95 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 4 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.38 69.72 72.61 74.92 78.96 79.90 83.80 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 5 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.47 87.62 88.91 91.22 92.91 95.94 (98) 101.1 102.9 106.4 107.9 112.4 114.8 118.7 121.8 127.6 126.9 131.3 55 56 57 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 6 Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 132.9 137.3 138.9 178.5 180.9 183.9 186.2 190.2 192.2 195.1 197.0 200.6 204.4 207.2 209.0 (209) (210) (222) 87 88 89 104 105 106 107 108 109 110 111 7 Fr Ra Ac Rf Db Sg Bh Hs Mt Ds Rg (223) (226) (227) (261) (262) (266) (264) (277) (268)? (272) 58 59 60 61 62 63 64 65 66 67 68 69 70 71 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu 140.1 140.9 144.2 (145) 150.4 152.0 157.3 158.9 162.5 164.9 167.3 168.9 173.0 175.0 90 91 92 93 94 95 96 97 98 99 100 101 102 103 Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr 232.0 231.0 238.0 (237) (244) (243) (247) (247) (251) (252) (257) (258) (259) (262)