I Name: ~ tt Lab Day and Time: Instructions 1. Do not open the exam until you are told to start. 2. This exam is closed note and closed book. You are not allowed to use any outside material while taking this exam. 3. Use the spaces provided to write down your answers. To receive full credit, you must show all work. Do not write answers on any other pieces of paper. If you need more room, write on the back of the exam and be sure to include a note describing where the work is located. 4. When solving numerical problems, make sure you include the proper units in your final answer as well as the proper number of significant digits. 5. If a question asks for a response in sentence or paragraph form, make sure you respond in that format. 6. Useful data for the exam and a periodic table are provided on the last page of the exam. Carefully tear out these sheets if you wish. Page # Points possible Points awarded 2-5 (MC) 39 5 10 6 22 7 15 8 10 Attendance 4 In-Class EC 4 Total 100 1
Chemistry 130 Exam #2-A October 28, 2015 Multiple Choice Unless otherwise directed, choose the single best answer for each question. When balancing chemical equations, use the smallest whole number coefficients. 1. Which of the following is the correct name for V(N02)2? a. vanadium nitrate b. vanadium nitrite c. vanadium(ii) nitride d. vanadium(ii) nitrate @ None of the above. 2. Which of the following is/are ionic compounds? CD> NH4IO II.) HCl III.) CF 4 <V I,V b. II, III, IV c. I, II, V d. I, II, IV, V IV.) NH 3. AlN 3. Use the unbalanced chemical equation shown below to answer the following question. If one molecule of O2 reacts, how many molecules of S02 will react? ~ ). S02(g) + 02(g) ~ 2S03(g) a. 1 molecule of S02 Cf) 2 molecules of S02 c. 3 molecules of S02 d. 4 molecules of S02 4. When Ba(Br03)2(aq) is mixed with Li3P0 4 (aq) a reaction occurs. What is the!!!!!! of all the coefficients for the balanced chemical equation for this reaction? Hint: If the balanced chemical equation was 2A + B ~ 3C, the sum of the coefficients would be 6. 12 b. 10 c. 7 d. 4 2
5. What is the oxidation state/number of chromium in H2Cr207? a. +2 b. +3 c. +5 @)+6 )..(H) \--~((.r) 'r 1(0') -= (6 :tcj') -\-2. Cc.v') lr 7 (-2,) ~; l. lr ;lev - 1<--( -.:::. ~ 2..&.:: \)... C.r ::: ~ OV- ~ (;. 6. When CsH120(1) is combusted, what is the ~ of all of the coefficients in the balanced chemical equation? Hint: If the balanced chemical equation was 2A + B -7 3C, the sum of the coefficients would be 6. a. 38 b. 13 c. 27 @39 7. When NaOH(aq) is mixed with H 3 P0 4 (aq) a reaction occurs. What is the sum of all the coefficients for the balanced chemical equation for this reaction? Hint: If the balanced chemical equation was 2A + B -7 3C, the sum of the coefficients would be 6. a. 4 '14- \ T- \ ~ 3 - ~ b. 6 (98 d. 10 8. Which of the following is the correct name for P20 S? G5 diphosphorus pentoxide b. potassium oxide c. potassium(v) oxide d. e. phosphorus oxide None of the above. 3
9. How many grams of silver are contained in a 0.0556 mole sample of silver? a. 1.78g b. 0.000515 g ~ 1.56 g 6.00g 10. Which of the following would you expect to be strong electrolytes when placed in deionized water? ~0""S A<.l ~. "t>ol~\c. \bv' I~ (it LiF UJ""-{J().. vwl ) Uij) HN03 III.) FeS a. I, II, III, IV, V b. I, II, III, V c. I, II, IV, V @) I, II, V IV.) @ HCN Ca(OH)2 11. A sample of2.00 moles of Ah(Cr207)3 contains how many moles of chromium? a. 3.00 moles 12.0moles c. 6.00 moles d. 2.00 moles 12. How many S02 molecules are there in a 115 g sample of S02? a. 5.58xl023 molecules b. 3.01xl0-24 molecules c. 6.02xl0 23 molecules d. 1.08x 10 24 molecules \ \ ~...--- \ 1'1 ::::-L 0 1> ~()~ )( \ U S0.L ".,J c-<..je.) z: \..0 \ bi.,\]-"'- $02. v--...jc:l.j~.:')
13. When N2 gas reacts with H2 gas, NH3 gas is formed. What is the ~ of all the coefficients for the balanced chemical equation for this reaction? Hint: If the balanced chemical equation was 2A + B -7 3C, the sum of the coefficients would be 6. a. 3 b. 4 c. 5 @6 e. 7 End of Multiple Choice 14. a. When aqueous lead(ii) nitrate reacts with aqueous nickel(i) iodide, what is the formula of the precipitate that is formed? (3 points) b. For the reaction above, what are the formulas of the spectator ions? (3 points) ) 15. What is the molar mass of Ptlvlnfra? (4 points) p-{; -, 3\Y.O\~ 6~ P~~CJ~ \ """,,v, p.(; V\v')D~ 0- ~... \ 0 \ \S.~~~'1 <). - -\\~\O 5
Chemistry 130 Exam #2-A October 28, 2015 16. In the table below, the name or formula for a chemical compound is given. Fill in the table with the corresponding name or formula of the chemical compound. (16 points) NAME FORMULA. lithium oxalate L~k (~O4 'o(of'l'\~ 1\<- ~kf\v~j~k. BrF5 "''1J.rI) ~\.o l \'L ~cjca HCI(aq) ammonium acetate tj~~(,l.\-\!0 L \O~~ ~c1c\ HI02(aq) ec:b~\t-cn) {\~~II'\\J..L silver thiosulfate barium hypochlorite A-Sl..$~03:, ~~(G\D '))-. CoN 17. What are the complete, total ionic, and net ionic equations for the reaction that occurs when an aqueous solution of HCI0 4 reacts with an aqueous solution of Ba(OH)2? Assume the reaction takes place in a beaker of deionized water. (6 points) Complete Total Ionic.z 1-\t;"j\ Ie ~(." ~ ~ ~ ;LOI\("1' --7 )JIl,-C.l(}o\ \.- ~ +-~ I -\ ~ \\-z.,0g<\ + ).. \i L()~) Net-Ionic Or- ~O~f\ -\- O~?\ ---? ;l.hl-cj")6
Chemistry 130 Exam #2-A October 28, 2015 18. a. In the space below, write the balanced chemical equation for what happens to H 2 S04(aq) when it is in deionized water. (2 points) b. Is the process above referred to as ionization or dissociation? (1 points) ~Of\\ t-q...~~ c. A sample of H 2 S04 is placed in a beaker of deionized water. In the diagram below, show the best representation of what will exist in the water if two H 2 S04 particles are placed in the beaker. (2 points) Beaker Full of Deionized Water 19. In a reaction, phosphorus starts with an oxidation state of -3. During the reaction, 5 electrons are transferred and phosphorus is oxidized. Use this information to fill out the half-equation below. Show what the phosphorus starts as and what it is converted into and put the transferred electrons on the correct side of the equation. (4 points) -~ p 20. What are the complete, total ionic, and net ionic equations for the reaction that occurs when an aqueous solution of Ab(S04)3 reacts with an aqueous solution of Cs 2 S? Assume the reaction takes place in a beaker of deionized water. (6 points) Complete Total Ionic ;ta\~~, ~ ~c:" >r Net-Ionic 7
21. A sample of Hs106 contains 9.25 grams of H. How many molecules of Hs106 are contained in the sample? (4 points) 'L:) (;,,,0"21)(\.U l4sr~ ~c.(.je).. 22. Use the balanced oxidation reduction reaction below to answer the following question. (6 points) 6HBr(aq) \\\0- &r a. Which element is reduced? b. Which element is oxidized? c. Which element is the reducing agent? d. Which element is the oxidizing agent? 1+ e. How many electrons are transferred? f. Which element are the electrons transferred to? 8