Chemistry 101 Exam 2 Practice Exam PDF

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This is a Chemistry 101 practice exam from October 20, 2022. The exam covers topics such as Lewis structures, bonding polarity, and molecular shapes of molecules. Chemistry concepts are tested across many questions.

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Chemistry 101 Exam 2 October 20, 2022 MGF Name________________________ ID#______________ TA___________ Lab Sec.______ Form 2 You have 1 hour to complete this exam and enter your answers on the answ...

Chemistry 101 Exam 2 October 20, 2022 MGF Name________________________ ID#______________ TA___________ Lab Sec.______ Form 2 You have 1 hour to complete this exam and enter your answers on the answer sheet. NO NOTES, BOOKS, OR ELECTONIC DEVICES OTHER THAN AN APROVED CALCULATOR MAY BE USED DURING THE EXAM. THIS EXAM WILL BE SCANNED! BUBBLE YOUR ANSWERS DARKLY. THIS IS YOUR ONLY EXAM BUBBLE SHEET. YOU WILL NOT BE GIVEN ANOTHER ONE. IF YOU CHOOSE TO USE PEN ON THE BUBBLE SHEET AND MAKE A MISTAKE, THERE IS NO WAY TO CORRECT IT. YOU HAVE BEEN WARNED. ONLY ANSWERS BUBBLES ON THE ANSWER FORM WILL BE GIVEN CREDIT. THE ENTIRE EXAM BOOKLET IS TO BE TURNED IN AT THE END OF THE EXAM! A Periodic Table and Information Sheets are provide separately This exam consists of 34 questions. All questions are worth 3 points each. There are 102 points available on this exam. Any point obtained in excess of 100 points may be considered to be extra credit. Do not spend too much time on a hard question. Come back to the hard one(s) after you have attempted all questions. There is no penalty for guessing. If any question appears ambiguous or unclear to you, please do not hesitate to raise your hand and ask for clarification. Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 1 Name________________________ ID#______________ TA___________ Lab Sec.______ 1. Idenitfy the Lewis structure of the selinium difluoride molecule (SeF2): A. B. F Se F F Se F C. D. F Se F F Se F F Se F F Se F E. F Se F 2. Rank the following bonds in order of increasing polarity: N-H, Br-O, C-Cl least polar most polar A. Br-O < N-H < C-Cl B. Br-O < C-Cl < N-H C. C-Cl < N-H < Br-O D. N-H < C-Cl < Br-O E. C-Cl < Br-O < N-H Page 2 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 3. What is the AXE classification for SF2? A. AX3E1 B. AX2E2 C. AX3E0 D. AX2E1 E. AX2E0 4. What is the geometry (electron geometry) around the central atom in the NO2- ion? A. linear B. trigonal pyramid C. tetrahedral D. trigonal planar E. bent Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 3 5. What is the molecular shape (molecular geometry) of the NH3 molecule? A. trigonal pyramid B. tetrahedral C. linear D. bent E. trigonal planar 6. What is the molecular shape (molecular geometry) of the SO2 molecule? A. trigonal planar B. trigonal pyramid C. tetrahedral D. bent E. linear Page 4 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 7. Classify the following as polar or nonpolar: [Select the one answer that is correct in all three columns.] CHF3 PF3 CCl4 --------------------------------------------------------------------------------------------------------- A. polar polar nonpolar B. polar nonpolar nonpolar C. nonpolar nonpolar polar D. polar nonpolar polar E. nonpolar polar nonpolar 8. Identify the strongest intermolecular force operating in the following substances: SO3 CH3OCH3 PCl3 A. dipole-dipole forces hydrogen bonds London dispersion forces B. London dispersion forces hydrogen bonds London dispersion forces C. London dispersion forces dipole-dipole forces Ionic bonds D. dipole-dipole forces hydrogen bonds dipole-dipole forces E. London dispersion forces dipole-dipole forces dipole-dipole forces Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 5 9. Arrange the following pure substances in order of increasing boiling point: CH3OH, CH3F, and CH3CH3 lowest b.p. highest b.p. A. CH3CH3 < CH3OH < CH3F B. CH3OH < CH3CH3 < CH3F C. CH3F < CH3OH < CH3CH3 D. CH3CH3 < CH3F < CH3OH E. CH3F < CH3CH3 < CH3OH Page 6 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 10. Which of the following lists the compounds in order of increasing boiling point? lowest boiling point highest boiling point A. OH < < B. OH < < C. OH < < D. OH < < E. OH < < 11. What mass of sodium has the same number of atoms as 15.00g of sulfur? A. 6.263 g B. 20.92 g C. 10.75 g D. 8.837 g E. 8.737 g Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 7 12. What is the mass of 0.6027 mole of potassium sulfate? A. 81.47 g B. 197.7 g C. 105.0 g D. 289.1 g E. 224.3 g 13. How many mole of copper(II) sulfate are present in 62.765 g of copper(II) sulfate? A. 2.543 mol B. 0.3932 mol C. 0.2455 mol D. 0.4370 mol E. 2.288 mol 14. Balance the following chemical equation using the lowest possible whole number coefficients: NH3 (g) + O2 (g) NO (g) + H2O (g) The coefficient for O2 (g) is: A. 1 B. 5 C. 2 D. 4 E. 6 Page 8 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 15. What is the maximum mass of nitric acid that can be prepared from 52.00g of H2O2 and excess N2H4 in the reaction N2H4 (l) + 7 H2O2 (aq) → 2 HNO3 (aq) + 8 H2O (l)? A. 27.52g B. 204.5g C. 192.7g D. 96.34g E. 31.48g 16. Identify the formula of the precipitate formed when aqueous solutions of lead(II) nitrate and potassium iodide are mixed: A. KNO3 B. PbO C. KIO3 D. PbI2 E. NI3 17. Consider what would happen if each of the following pairs of solutions were mixed: mixture 1: Ni(NO3)2 (aq) + Na2CO3 (aq) → mixture 2: BaCl2 (aq) + CuSO4 (aq) → mixture 3: K3PO4 (aq) + NaC2H3O2 (aq) → Which of these mixture will produce a precipitate? (Hint: Complete the equations.) [Choose the one answer that is correct in all three columns.] mixture 1 mixture 2 mixture 3 A. no reaction precipitate precipitate B. precipitate precipitate precipitate C. precipitate precipitate no reaction D. no reaction no reaction precipitate E. precipitate no reaction no reaction Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 9 18. Using the smallest possible whole number coefficients, write a balanced chemical equation for the neutralization reaction between potassium hydroxide and sulfuric acid. What is the coefficient in front of H2O (l)? A. 3 B. 4 C. 2 D. 1 E. 6 19. Identify the gas formed when a solution of hydrochloric acid reacts with solid sodium carbonate. A. Cl2 (g) B. CO2 (g) C. H2 (g) D. NaCl (g) E. O2 (g) 20. Consider the following oxidation-reduction reaction KClO3(aq) + 6 HBr(aq) → 3 Br2(l) + 3 H2O(l) + KCl(aq) What element is oxidized in this reaction? A. bromine B. hydrogen C. oxygen D. potassium E. chlorine 21. Consider the following oxidation-reduction reaction: 2 Ni(OH)2 (s) + N2H4 (aq) 2 Ni (s) + N2 (g) + 4 H2O (l) Identify the reducing agent in this reaction. A. Ni B. N2 C. Ni(OH)2 D. N2H4 E. H2O Page 10 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 22. Classify each of the following as an oxidation or a reduction [Select the one answer that is correct in all three columns.] ------------------------------------------------------------------------------------------------------------------- A. reduction reduction oxidation B. oxidation reduction oxidation C. oxidation oxidation oxidation D. oxidation oxidation reduction E. reduction oxidation reduction 23. According to the reaction progress diagram above, what is the value of the activation energy for the forward reaction? A. -125.0 kcal B. 50.0 kcal C. -50.0 kcal D. 125.0 kcal E. 175.0 kcal Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 11 24. The following reaction energy diagrams are for reactions described by the equation A (g) + B (g) AB (g) If all reactions are run at 25.0 °C with initial concentrations of [A] = 0.500 M and [B] = 0.500 M, which of these reactions will have the fastest rate in the forward direction? A. B. C. D. E. 25. Which of the following must be the same at equilibrium? I. the number of gas molecules on each side of the reaction. II. the rate of the forward reaction and the rate of the reverse reaction. III. the concentration of the reactants and the concentration of the products. A. II only B. I and III C. I and II D. III only E. II and III Page 12 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 26. Identify the equilibrium equation associated with the following reaction: 4 CH4 (g) + S8 (s) 4 CS2 (g) + 8 H2 (g) A. B. C. 4 8 4 8 4 8 K= [CS2 ] [H2 ] K= [CS2 ] + [H2 ] K= [CS2 ] [H2 ] 4 4 4 [CH4 ] [S8 ] + [CH4 ] [S8 ][CH4 ] D. E. 4 8 K= [ 4CS2 ][8H2 ] [CS2 ] + [H2 ] K= [S8 ][ 4CH4 ] [CH4 ] 4 27. Consider the reaction system N2 (g) + 3 H2 (g) 2 NH3 (g) ∆H = –22.1 kcal Will the equilibrium shift toward products or toward reactants when each of the following changes is made? [N2] is added the temperature is raised the volume is decreased A. shifts toward reactants shifts toward reactants shifts toward products B. shifts toward products shifts toward reactants shifts toward reactants C. shifts toward products shifts toward reactants shifts toward products D. shifts toward reactants shifts toward products shifts toward products E. shifts toward products shifts toward products shifts toward reactants Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 13 28. Graphite has a specific heat of 2.036 cal/g°C. When 312.5 cal of heat energy are applied to a sample of graphite, the temperature of the graphite increases from 28.21°C to 76.87°C. What is the mass of this sample of graphite? A. 56.33 g B. 7469 g C. 3.154 g D. 6.055 g E. 13.08 g 29. Classify the following processes as endothermic or exothermic. Condensation Sublimation Vaporization A. endothermic endothermic exothermic B. exothermic endothermic exothermic C. endothermic exothermic exothermic D. exothermic endothermic endothermic E. exothermic exothermic endothermic 30. Examine the heating curve for water: 150 125 100 75 50 Temperature 25 (°C) 0 –25 –50 Heat added The phase(s) of water present during the segment of the curve indicated is (are): A. liquid only B. liquid and gas C. gas only D. solid and liquid E. solid only Page 14 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 31. 200.0 g of oxygen gas are sealed in a 65.00 L tank at a temperature of 75.00 °C. What is the pressure inside the tank? A. 18.94 atm B. 1.373 atm C. 2.747 atm D. 0.2959 atm E. 0.5918 atm 32. A solution of cobalt chloride has a concentration of 6.345 g/L. If 11.85 mL of this solution are diluted by adding 19.37 mL of water, what is the final concentration of the diluted solution? A. 4.002 g/L B. 6.345 g/L C. 3.882 g/L D. 2.408 g/L E. 10.37 g/L Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF Page 15 33. The following plot shows the relationship between the density of a solution of X and the concentration of the solution: Based on this plot, what is the concentration of the solution of X with a density of 1.044g/mL? A. 61.1 g/L B. 67.3 g/L C. 76.0 g/L D. 45.0 g/L E. 30.2 g/L Page 16 Chemistry 101 Exam 2 Form 2 October 20, 2022 MGF 34. 12.00g of a mixture of NaNO3 and Ba(NO3)2 are dissolved in water. A solution of Na3PO4 is added until no further precipitation is observed. The reaction is: 3 Ba(NO3)2 (aq) + 2 Na3PO4 (aq) Ba3(PO4)2 (s) + 6 NaNO3 (aq) The Ba3(PO4)2 precipitate is filtered, dried and found to have a mass of 3.920g. What is the mass % of barium nitrate in the original mixture? [Molar masses: Ba(NO3)2 = 261.32g/mol, Ba3(PO4)2 = 601.84g/mol, NaNO3 = 85.00g/mol] A. 25.08% B. 42.55% C. 32.67% D. 75.23% E. 14.18% Ba(NO3)2 Ba(NO3)2 Ba(NO3)2 Ba(NO3)2 Ba(NO3)2 Answers # ID Points Type 2 1 C101 E1 FALL 2023 1 3.00 MCS A 2 C101 E1 FALL 2023 2 3.00 MCS E 3 C101 E2 FALL 2023 1 3.00 MCS B 4 C101 E2 FALL 2023 2 3.00 MCS D 5 C101 E2 FALL 2023 3 3.00 MCS A 6 C101 E2 FALL 2023 4 3.00 MCS D 7 C101 E2 FALL 2023 5 3.00 MCS A 8 C101 E2 FALL 2023 6 3.00 MCS E 9 C101 E2 FALL 2023 7 3.00 MCS D 10 C101 E2 FALL 2023 8 3.00 MCS C 11 QUESTION 9.5 8 3.00 MCS C 12 QUESTION 9.5 9 3.00 MCS C 13 C101 E2 FALL 2023 9 3.00 MCS B 14 C101 E2 FALL 2023 10 3.00 MCS B 15 C101 E2 FALL 2023 11 3.00 MCS A 16 C101 E2 FALL 2023 12 3.00 MCS D 17 C101 E2 FALL 2023 13 3.00 MCS C 18 C101 E2 FALL 2023 14 3.00 MCS C 19 C101 E2 FALL 2023 15 3.00 MCS B 20 C101 E2 FALL 2023 16 3.00 MCS A 21 C101 E2 FALL 2023 17 3.00 MCS D 22 C101 E2 FALL 2023 18 3.00 MCS D 23 C101 E2 FALL 2023 19 3.00 MCS B 24 C101 E2 FALL 2023 20 3.00 MCS A 25 C101 E2 FALL 2023 21 3.00 MCS A 26 C101 E2 FALL 2023 22 3.00 MCS A 27 C101 E2 FALL 2023 23 3.00 MCS C 28 C101 E2 FALL 2023 24 3.00 MCS C 29 C101 E2 FALL 2023 25 3.00 MCS D 30 C101 E2 FALL 2023 26 3.00 MCS D 31 C101 E2 FALL 2023 27 3.00 MCS C 32 C101 E2 FALL 2023 41 3.00 MCS D 33 C101 E2 FALL 2023 42 3.00 MCS B 34 C101 E2 FALL 2023 43 3.00 MCS B SECTION 1 ( 34 items) 102.00 The Solubility Rules 1. All sodium, potassium, lithium and ammonium salts are soluble. 2. All nitrates, acetates, chlorates and perchlorates are soluble [Silver acetate is slightly soluble] 3. All silver, lead and mercury salts are insoluble. [Mercury(II) chloride is soluble. Mercury(II) bromide is slightly soluble.] 4. All chlorides, bromides and iodides are soluble. 5. All carbonates, phosphates, sulfides, and oxides are insoluble. 6. All hydroxides are insoluble. [Barium hydroxide and strontium hydroxide are soluble, calcium hydroxide is slightly soluble] 7. All sulfates are soluble. [Except those of barium, strontium and calcium] = CsCmCÄT PV=nRT R = 0.0820575 = 62.3637 = 8314,48 X °C = (X + 273.15) K 1.00000 atm = 760.000 torr = 101325 Pa

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