Download CHEM 103 Exam 1: Empirical Formulas & Calculating Chemical Quantities - Prof. Gerald R. Mi and more Exams Chemistry in PDF only on Docsity! CHEM 103 Hour Exam 1 NAME(PRINT)_ 28 February 2002 8:00 A.M. SECTION 3 1_ _ Dr. Miller LAB TA's Name: SHOW ALL OFYOUR WORK! If you must continue your work on a problem in another place, please indicate in the space provided for the question where your work is continued. Clearly mark you answers. You may remove the periodic table attached as the last page of the exam if you wish, but please do NOT separate the pages of the exam. HONOR PLEDGE WORDING: I PLEDGE ON MY HONOR THAT I HAVE NOT GIVEN OR RECEIVED ANY UNAUTHORIZED ASSISTANCE ON THIS EXAMINATION. PLACE TO WRITE HONOR PLEDGE BY HAND: PLACE FOR SIGNATURE OF STUDENT 1. ___718 2. ___722 3. ___722 4. ___722 5. ___716 TOTAL 7100 1. (18 pts) A compound is analyzed and found to be 62.93% lead, 0.612% hydrogen, 7.30% carbon, and 29.16% oxygen. Determine the empirical formula of this compound. Answer: 4. (22 pts) Short problems a. (8 pts) When Jonathan adds a solution containing 4.555 g of AgNO3 (169.87 g/mole)to a solution containing excess Na2S (78.05 g/mole), he recovers 3.224 g of the insoluble salt Ag2S (247.80 g/mole). Calculate the percent yield Jonathan obtained. Answer: b. (6 pts) The temperature of a sample is 455 °F 1) What is the temperature on the Celsius scale? Answer: 2) What is the temperature on the Kelvin scale? Answer: c. (8 pts) A sample of the element thallium, Tl, recovered from a nuclear reactor is 47.50% 203T1 (202.9723 amu) and 52.50% 205T1 (204.9745 amu). Determine the atomic weight of this sample of thallium. Answer: 5. (16 pts) Short answer questions (work not graded, only the answer will be graded) a. Fill in the missing name or missing formula (including charge!): Name Formula tin (IV) ion ________ magnesium ion oxalate ion carbonate ion NCV" OH1 ' Cr3+ MnCV b. Which of the following are heterogeneous and which are homogeneous? pure air salt water block of wood concrete block :. Which of the following properties of a liquid are intensive and which are extensive? mass density temperature volume PERIODIC TABLE I 6 ]> 2: 1 ] 3< F 8^ « c 13 8 F (2 3 A 94 1 Ja 3.0 9 K J.I 17 tb 5.5 5 : s 2.9 7 > 23) 4 Be 9.01 12 Mg 24.3 20 Ca 40.1 38 Sr 87.6 56 Ba 137.3 88 Ra (226) 21 Sc 45.0 39 Y 88.9 57 La 138.9 89 Ac (227) 22 Ti 47.9 40 Zr 91.2 72 Hf 178.5 104 Rf (259) 23 V 50.9 41 Nb 92.9 73 Ta 180.9 105 Db 24 Cr 52.0 42 Mo 95.9 74 w 183.9 106 Sg 25 Mn 54.9 43 Tc (97) 75 Re 186.2 107 Bh 26 Fe 55.8 44 Ru 101.1 76 Os 190.2 108 Hs 27 Co 58.9 45 Rh 102.9 77 Ir 192.2 109 Mt 28 Ni 58.7 46 Pd 106.4 78 Pt 195.1 29 Cu 63.5 47 Ag 107.9 79 Au 197.0 30 Zn 65.4 48 Cd 112.4 80 Hg 200.6 5 B 10.8 13 Al 27.0 31 Ga 69.7 49 In 114.8 81 Tl 204.4 6 C 12.01 14 Si 28.1 32 Ge 72.6 50 Sn 118.7 82 Pb 207.2 7 N 14.01 15 P 31.0 33 As 74.9 51 Sb 121.8 83 Bi 209.0 8 o 16.00 16 s 32.1 34 Se 79.0 52 Te 127.6 84 Po 209 9 F 19.0 17 Cl 35.5 35 Br 79.9 53 I 126.9 85 At |_(2io) 2 He 4.00 10 Ne 20.2 18 Ar 39 9 36 Kr 83.8 54 Xe 131.3 86 Rn (222) 58 Ce 140.1 59 Pr 140.9 60 Nd 144.2 61 Pm (147) 62 Sm 150.4 63 Eu 152.0 64 Gd 157.3 65 Tb 158.9 66 Dy 162.5 67 Ho 164.9 68 Er 167.3 69 Tm 168,9 70 Yb 173.0 71 I.ll 175.0 90 Th 232.0 91 Pa (231) 92 U 238.0 93 Np (237) 94 Pu (244) 95 Am (243) 96 Cm (248) 97 Bk (247) 98 Cf (251) 99 Es (254) 100 Fm (257) 101 Md (258) 102 No (255) 103 T,r (257)
