Name (printed): Signature:

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1 CHEM Lab Section Number: Name (printed): Signature: This exam consists of 36 questions all of equal value for a total of 225 points. Make sure that your test has all of the pages. Please read each problem carefully. There are no intentionally misleading questions; each problem should be taken at its face value. Please mark your answers on the Scantron sheet provided to you and on the actual exam. You will be given a periodic table and an exam information sheet to use during the exam. You may remove it from the exam make it more accessible. You may also use the designated Casio fx-300ms-plus calculator or equivalent non-programmable non-graphing scientific calculator during the exam. Use the back pages of the test as scratch paper. You are not allowed to use any devices capable of accessing the internet, textbooks, notes, or homemade reference sheets during the exam. You may leave if you finish the exam early. Give the exam and the information sheet to your TA and leave quietly without disturbing other students. Before leaving, check that all your answers have been properly entered on the Scantron sheet and the exam and that your name is written on every page of the exam and on the Scantron sheet. All cell phones and electronic devices must be turned off and put away. Please remove all hats and caps. Place your books and all papers out of sight under your seat. If the TA believes that you might be looking at your neighbor s paper, you will be asked to move to a new location. Exam scores will be posted on Blackboard as soon as the grading is complete. Your test will be returned to you in the first lab meeting of next week. If you have any questions regarding the grading of your exam, please notify your TA. The time available for the exam is 120 minutes. Good luck! 1 of 9

2 Name: Lab Section #: Please mark your answers on the scantron sheet using a #2 pencil and also mark your answers on the exam itself. Mark Test From A on your scantron. 1. Tetraphosphorus hexoxide is formed by the reaction of phosphorus with oxygen gas. If a mixture of 75.3 g of phosphorus and 38.7 g of oxygen produce 43.3 g of P4O6, what is the percent yield for the reaction (NOTE: the reaction is not balanced)? (a) 48.8% (b) 57.5% (c) 38.0% (d) 32.4% (e) 16.3% P4(s) + O2(g) P4O6(s) 2. Aluminum metal reacts with chlorine gas to form solid aluminum chloride, AlCl3. What mass of chlorine gas is needed to react completely with 163 g of aluminum? (a) 642 g (b) 214 g (c) 245 g (d) 321 g (e) 489 g 3. How many molecules of molecular oxygen react with four molecules of NH3 to form four molecules of nitrogen monoxide and six molecules of water? (a) 10 (b) 3 (c) 4 (d) 5 (e) 2 4. Balance the following equation: C8H18O3(l) + O2(g) H2O(g) + CO2(g) (a) C8H18O3(l) + 11O2(g) 9H2O(g) + 8CO2(g) (b) 2C8H18O3(l) + 22O2(g) 9H2O(g) + 16CO2(g) (c) C8H18O3(l) + 13O2(g) 18H2O(g) + 8CO2(g) (d) 2C8H18O3(l) + 17O2(g) 18H2O(g) + 16CO2(g) (e) C8H18O3(l) + 8O2(g) 9H2O(g) + 8CO2(g) 2 of 9

3 5. Hydroxylamine hydrochloride is a powerful reducing agent which is used as a polymerization catalyst. It contains 5.80 mass % H, mass % N, mass % O, and mass % Cl. What is its empirical formula? (a) H2N7O8Cl18 (b) H2N2O2Cl (c) HN3O4Cl9 (d) H4NOCl2 (e) H4NOCl 6. Household sugar, sucrose, has the molecular formula C12H22O11. What is the % of carbon in sucrose, by mass? (a) 42.1% (b) 26.7% (c) 41.4% (d) 52.8% (e) 33.3% 7. The number of hydrogen atoms in mol of C3H8O3 is (a) H atoms (b) H atoms (c) H atoms (d) H atoms (e) H atoms 8. Which of the following samples contains the greatest total number atoms? (a) 75.0 g of CaO (b) 50.0 g Li2O (c) 50.0 g CO2 (d) g Fe2O3 (e) g of SO3 9. Hydroxylamine nitrate contains mass % N, 4.20 mass % H, and mass % O. If its molar mass is between 94 and 98 g/mol, what is its molecular formula? (a) NH2O5 (b) N3H3O3 (c) N4H8O2 (d) N2H2O4 (e) N2H4O4 3 of 9

4 10. Select the classification for the following reaction. (a) Decomposition (b) Combination (c) Displacement (d) Precipitation (e) Acid-base neutralization 2Ag + (aq) + Zn(s) 2Ag(s) + Zn 2+ (aq) 11. Lithium hydroxide is used in alkaline batteries. Calculate the molarity of a solution prepared by dissolving moles of LiOH in enough water to give a final volume of 750. ml. (a) M (b) 1.99 M (c) 1.50 M (d) 1.12 M (e) M 12. Which of the following is a strong acid? (a) HClO4 (b) HF (c) H3PO4 (d) CH3COOH (e) KOH 13. Perform the following calculation: (a) 4 (b) 3.3 (c) 3.27 (d) (e) ( ) 3.2 =? 14. Which of the following is Not a metal? (a) Ga (b) In (c) Zn (d) Ge (e) Ti 4 of 9

5 15. Which answer includes all the following that are chemical changes and not physical changes? I. Milk goes sour II. Jewelry tarnishes III. Butter melts on warm toast IV. Clay is molded into a new shape V. Your body digests food (a) III and IV (b) III and V (c) I, II, III, IV, and V (d) I, II, IV and V (e) I, II, V 16. Which one of the following is most likely to be an ionic compound? (a) NH3 (b) InCl3 (c) CH2Cl2 (d) CH3OH (e) H2O 17. Five peseta coins from Spain were dropped into a graduate cylinder containing ml of water. The volume of water increased to ml. A single coin has a mass of 0.99 gram. What is the identity of the metal used for the Spanish 1 peseta coins? (Density of aluminum=2.7 g/ml, density of zinc=7.1 g/ml, density of copper=9.0 g/ml, density of silver=10.0 g/ml, density of nickel=8.91 g/ml) (a) Aluminum (b) Zinc (c) Copper (d) Silver (e) Nickel 18. Rubidium has two naturally occurring isotopes, 85 Rb with an atomic mass of amu and 87 Rb with an atomic mass of amu. The atomic mass of boron is (from the periodic table). The percent abundances of the boron isotopes are % 85 Rb and % 87Rb. (a) 82.00, (b) 75.00, (c) 72.15, (d) 15.50, (e) 77.15, of 9

6 19. The correct symbol for the element Manganese is: (a) Mo (b) Mn (c) Mg (d) V (e) W 20. Looking at the above rifle target, how would you describe the shooting of this contestant? (a) Inaccurate and precise (b) Accurate and imprecise (c) Accurate and precise (d) Inaccurate and imprecise (e) None of the above 21. What is the formula for calcium nitrite? (a) CaNO2 (b) Ca(NO2)2 (c) Ca(NO3)2 (d) CaNO3 (e) Ca(NO3)3 22. What is the name of H2SO4? (a) hydrogen sulfuric acid (b) sulfuric acid (c) hydrogen sulfurous acid (d) dihydrogen sulfurous acid (e) sulfurous acid 23. Which of the following ions does Not have a 1 charge? (a) chloride (b) sulfate (c) hydroxide (d) nitrate (e) acetate 24. How many milliliters of 2 M NaCl solution are required to make 1 L of 0.4 M NaCl solution? (a) 5000 ml (b) 800 ml (c) 500 ml (d) 200 ml (e) 20 ml 6 of 9

7 25. One mole of (NH4)2HPO4 contains numbers of hydrogen atoms (a) 6.02 x (b) x (c) 3.01 x (d) x (e) x Group atoms tend to lose electrons when they form ionic compounds? (a) Group 1A and 2A (b) Group 3A and 4A (c) Group 4A and 5A (d) Group 6A and 7A (e) Group 7A and 8A 27. Identify the correct molecular formula for the chlorate ion? (a) ClO (b) ClO2 (c) ClO3 (d) ClO4 (e) Cl 28. Automobile batteries use 3.0 M H2SO4 as an acid. How much 1.20 M NaOH will be needed to neutralize 225 ml of battery acid? (a) 1.1 L (b) L (c) 0.90 L (d) M (e) M H2SO4(aq) + 2NaOH(aq) 2H2O(l) + Na2SO4(aq) 29. What is the molecular formula for a compound that is 46.16% carbon, 5.16% hydrogen and 48.68% fluorine if the molar mass of this compound is g? (a) C3H4F2 (b) C5H10F5 (c) C6H8F4 (d) C6H6F3 (e) C6H10F4 7 of 9

8 30. What is the concentration of all ions, in parts per million, if 0.02 gram of Na3PO4 is dissolved in 1000 ml of water (water density is 1 g/ml)? (a) 20 ppm (b) 40 ppm (c) 60 ppm (d) 80 ppm (e) 100 ppm 31. Select the precipitate that forms when aqueous ammonium sulfide reacts with aqueous copper(ii) nitrate. (a) NH4(NO3)2 (b) NH4NO3 (c) CuSO4 (d) CuS (e) Cu2S 32. A standard solution of M NaOH was used to determine the concentration of a hydrochloric acid solution. If ml of NaOH is needed to neutralize ml of the acid, what is the molar concentration of the acid? (a) 2.26 M (b) M (c) M (d) 1.12 M (e) 2.43 M 33. Which one of the following is not a redox reaction? (a) Cl2(g) + 2KBr(aq) Br2(l) + 2KCl(aq) (b) Zn(s) + H2SO4(aq) ZnSO4(aq) + H2(g) (c) H2O(l) + NH3(g) NH4 + (aq) + OH (aq) (d) 2H2(g) + O2(g) 2H2O(l) (e) All of the above are redox reactions 34. Select the best statement relating to the following reaction: 2MnO2(s) + KClO3(aq) + 2KOH(aq) 2KMnO4(aq) + KCl(aq) + H2O(l) (a) O in KClO3 is the oxidizing agent. (b) K in KClO3 is the reducing agent. (c) H in KOH is oxidized. (d) Mn in MnO2 is oxidized. (e) Cl in KClO3 is the reducing agent. 8 of 9

9 35. What is the oxidation number of Cl in KClO4? (a) 1 (b) +7. (c) +1 (d) 0 (e) Which one of the following is a redox reaction? (a) H2O(l) H + (aq) + OH (aq) (b) Na2CO3(s) + 2HCl(aq) 2NaCl(aq) + CO2(g) + H2O(l) (c) K2Cr2O7(aq) + 2KOH(aq) 2K2CrO4(aq) + H2O(l) (d) Ba 2+ (aq) + SO4 2 (aq) BaSO4(s) (e) 2Na(g) + Cl2(g) 2NaCl(s) 9 of 9