Name: Chemistry 400: General Chemistry Miller Exam I September 20, 2017 Approximately 150 points

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Name: Chemistry 400: General Chemistry Miller Exam I September 20, 2017 Approximately 150 points Please answer each of the following questions to the best of your ability.

For multiple choice, please clearly mark the correct answer. Good luck! I. Multiple Choice / Fill in the blank (4 points each, 40 points total) 1. When the ph of a solution changes from 2.00 to 4.

The concentration of hydrogen ions increases by a factor of 100. D. The concentration of hydrogen ions decreases by a factor of 100. 2. Isotopes differ in the number of what particle? A.

2 TiO 2 (s) + 3 C(s) + 4 Cl 2 (g) 2 TiCl 4 (g) + CO 2 (g) + 2 CO(g) A. 2 mol B. 6 mol C. 0.75 mol D. 3 mol E. 1.33 mol 4. The drawings below represent flasks of aqueous solutions.

1 Name: Chemistry 400: General Chemistry Miller Exam I September 20, 2017 Approximately 150 points Please answer each of the following questions to the best of your ability. If you wish to receive partial credit, please show your work. For multiple choice, there is no partial credit (unless otherwise noted) and there is only one correct answer. For multiple choice, please clearly mark the correct answer. Good luck! I. Multiple Choice / Fill in the blank (4 points each, 40 points total) 1. When the ph of a solution changes from 2.00 to 4.00, which one of the following is TRUE? A. The concentration of hydrogen ions increases by a factor of 2. B. The concentration of hydrogen ions decreases by a factor of 2. C. The concentration of hydrogen ions increases by a factor of 100. D. The concentration of hydrogen ions decreases by a factor of Isotopes differ in the number of what particle? A. beta particles B. protons C. electrons D. neutrons E. gamma particles If 2 mol of C(s) reacted according to the following equation, what quantity of TiCl 4 would result? 2 TiO 2 (s) + 3 C(s) + 4 Cl 2 (g) 2 TiCl 4 (g) + CO 2 (g) + 2 CO(g) A. 2 mol B. 6 mol C mol D. 3 mol E mol 4. The drawings below represent flasks of aqueous solutions. Each shaded dot represents a dissolved solute particle. If you place solution D in a 500 ml flask and dilute to a volume of 500 ml, which flask best represents the new solution? A. Solution A B. Solution B C. Solution C D. Solution D E. Solution E F. Solution F Solution A 500 ml Solution B 500 ml Solution C 500 ml Solution D 250 ml Solution E 250 ml Solution F 250 ml 1

2 5. A compound consists of only C and F. It contains 38.71% C by mass. What is the empirical formula of the compound? A. CF B. CF 2 C. CF 3 D. C 2 F E. CF 4 For problems 6 and 7: Aqueous solutions of BaCl2 and AgNO3, are mixed. BaCl 2 + AgNO 3 AgCl + Ba(NO 3 ) 2 (unbalanced reaction with no phases!) 6 The balanced total ionic equation (TIE) contains which one of the following terms? A. 2 Ba 2+ (aq) B. Cl (aq) C. 2 Ag + (aq) D. NO 3 (aq) E. AgCl(aq) 7. The net ionic equation (NIE) contains which one of the following terms? A. Ag + (aq) B. Ba 2+ (aq) C. NO 3 (aq) D. H + (aq) E. AgCl(aq) 8. The oxidation state of iodine in IO 3 is: A. 0 B. +3 C. 3 D. +5 E The action level for copper in drinking water is 1.3 ppm Cu. To which one of the following is this equivalent? A. 1.3 x 10 3 ppm B. 1.3 g/ml C. 1.3 mg/l D. 1.3 µg/l 10. In the reaction 2 Ca(s) + O 2 (g) 2 CaO(s), which species is oxidized? A. O 2 B. O 2 C. Ca D. Ca 2+ E. none of these 2

3 II. Nomenclature If the name is given, please give the formula. If the formula is given, please give the name. (4 points each, 24 points total, spelling counts) A. BaBr 2 B. O 3 F 2 C. Na 2 CO 3 10H 2 O D. Pb(CN) 2 E. KClO 4 F. CH 3 CH 2 OH III. Free Response 1. For each of the following compounds, write the formula on a line under the picture that most closely describes what would happen when each compound is dissolved in water. (12 points) A. NaCl B. CH 3 OH C. NH 4 CH 3 COO D. CH 3 CH 2 COOH bulb unlit bulb dimly lit bulb brightly lit 3

4 2. In the following reaction, there are 2.54 g of Cr(NO 3 ) 3 and ml of M H 2 S. 2 Cr(NO 3 ) 3 (aq) + 3 H 2 S(aq) Cr 2 S 3 (s) + 6 HNO 3 (aq) A. How many grams of Cr 2 S 3 can be made? As part of your work for this problem, show all calculations to prove which one is the limiting reactant. (12 points) B. How many grams of the excess reactant are left over? (10 points) 4

5 3. What is the concentration of NaOH solution that requires 27.5 ml to titrate 50.0 ml of M H 2 SO 4? (8 points) H 2 SO 4 (aq) + 2 NaOH(aq) 2 H 2 O(l) + Na 2 SO 4 (aq) 4. A student wishes to prepare a solution of (NH 4 ) 2 SO 4. What mass of (NH 4 ) 2 SO 4 would be required to prepare ml of a 6.00 M solution? (6 points) 5. For HCl and CH 3 COOH, please complete the following table: Type of acid (strong or weak) (4 points) Percent ionized when in solution (answer should include a number) (4 points) For M solutions of each acid, has a higher [H + ] (put an X in one box) (2 points) For M solutions of each acid, has a higher ph (put an X in one box) (2 points) HCl 5 CH3COOH

6 6. A g sample of unknown is analyzed by combustion analysis and produces g of CO 2 and g of H 2 O. A separate g sample of the unknown produces g of NH 3. The compound has four elements (C a H b N c X d ) but the fourth element is unknown. A. Find the ratio of the moles of C, H, and N in the compound (similarly to what was done in class). (14 points) B. Find the complete empirical formula including the moles and the identity of the fourth element. To help you identify the fourth element, when the unknown compound is put in an aqueous solution with aqueous silver nitrate, a precipitate forms. when the unknown compound is put in an aqueous solution with aqueous iron (III) nitrate, a precipitate does not form. (10 points) 6

Name. Practice Test 2 Chemistry 111

Name. Practice Test 2 Chemistry 111 Name Practice Test 2 Chemistry 111 1) In the aqueous reaction of K 2 SO 4 (aq) + Ba(NO 3 ) 2 (aq) BaSO 4 (s) + 2KNO 3 (aq), which ions are the spectator ions? A) Ba 2+ 2- and SO 4 B) Ba 2+ and K + C) Ba