Chemistry 111 Exam2

. , Name __CRIВ ------- Chemistry 111 Section ----- ЕХАМП ТА ------------ Directions: 1. Each student is responsiЫe for following directions. Read this page carefully. 2. Write your name and other requested inforrnation on this page and on the separate answer sheet. .) . ,., CODE your name on the answer sheet using an ordinary (#2) pencil. 4. CODE your correct 10-digit identification number (PUID) on the answer sheet. THIS IS VERY IMPORTANT! 5. CODE your section number on the answer sheet. Please use all four digits, 0101, 0102, 0201, etc. This is also very important! 6. Put all calculations on the examination pages. DO NOT PUT ANY EXTRA МАRКS ON ТНЕ COMPUTER ANSWER SHEET! 7. This exam consists of 25 multiple-choice questions worth 5 points each. Choose the one best or correct answer for each question and write it both on your exam paper and on the computer answer sheet. The computer answer sheet is the only one that will Ье graded! 8. This exam consists of 6 pages plus а Periodic ТаЫе. Please check to Ье sure that you have them all! Avogadro's number = 6.022 х 1023 END OFEXAM 1) Please make sure that you have entered 25 answers on your scan sheet. 2) Make sure that you have entered your name, ID number, and lab section number (4 digits). 3) You MUST turn the scan sheet in to your ТА before leaving the exam! С 1. How many atoms of carbon are present in1.000 mg of carbon? (а) 2.507х 10 16 atoms (Ь) 2.507х 10 19 atoms (с) 5.014х 1 О 19 atoms 2.507х 10 22 atoms 5.014х 10 22 atoms (d) (е) А D 2. 3. Which of the following contains the largest number of hydrogen atoms? (а) 1.000 mol Н 2 (Ь) . 0.1000 mol СН4 (с) 0.2000 mol Н 2 0 (d) 6.022 х 10 23 hydrogen atoms (е) 0.2000 molNН4Cl Determine the mass of 1.27 mol Mg(OH)2. (а) (Ь) (с) (d) (е) с 4. 5. g g g g g How many grams ofKCl (М. М =-74.6 g/mol) are needed to prepare 500. mL of а0.200 М KCI solution? (а) (Ь) (с) (d) (е) D 47.6 52.5 66.1 74.1 82.4 5.31 6.78 7.46 8.52 9.34 g g g g g Which of the following solutions contains the greatest amount ofNaCI? (а) 500. mL of0.100 М NaCl solution (Ь) 100. mL of0.500 М NaCl solution (с) 1.00 L of0.0800 М NaCl solution (d) 0.200 L of2.00 М NaCl solution (е) 50.0 mL of5.00 М NaCl solution 2 ' . D 6. Which of the following stock solutions can Ье diluted to Ье 200. mL of а 0.100 М HCl Ьу adding water? (а) (Ь) (с) (d) (е) D 7. 10.0 mL of а 1.00 М HCl 20.0 mL of а 0.900 М НС! 40.0 mL of а 0.800 М HCl 50.0 mL of а 0.400 М НС! 100. mL of а 0.300 М НС! During Rutherford's gold foil experiment, the following observations were made: (i) (ii) (iii) Most of the alpha particles went through the gold foil. Some alpha particles were deflected as they went through the foil. А small number of the alpha particles bounced backward. This experiment proved that: (а) (Ь) (с) (d) (е) А 8. alpha particles are positively charged. electrons have wave-like characters. the nucleus is composed of protons and neutrons. an atom's mass is nearly all in its tiny, positively charged nucleus. electrons of an atom exist only in specific spherical orbits. The following picture shows electromagnetic waves for the red light and the Ыuе light. Based on this picture, choose а сопесt statement. . vv (\ (\ (\ (\ \ГV Blue light Red light (а) (Ь) (с) (d) (е) С 9. l О. The Ыuе light has а higher frequency than the red light. The Ыuе light has а lower energy than the red light. The Ыuе light has а longer wavelength than the red light. The Ыuе light can Ье considered as а particle (photon) but the red light cannot. The Ыuе light travels faster than red light. Which of the following statements regarding electronic structure is NOT true? (а) (Ь) (с) (d) (е) Е distance The third energy level (n = 3) has three suЫevels and nine orbitals. The second energy level (n = 2) can accommodate а maximum of 8 electrons. The 1s and 2s orЬital have the same energy but different sizes. The d suЬlevel has 5 orЬitals that have the same energy. Only two electrons with opposite spin are allowed per orЬital. Which of the following shows the сопесt Lewis symbol (that is, the number of valence electrons and their arrangement) for the given element? (а) (Ь) (с) • • : s: (d) ·AI (е) •• • N. . 4 Е 11. The electron configuration ofElement А is 1s22s22p4 . How many valence and unpaired electrons doesElement А have? (Hint: Draw Lewis symbols or orbital diagrams). (а) (Ь) (с) ( d) (е) в А В В 12. 13. 14. 15. Valence electrons 2 4 4 6 6 Unpaired electrons 1 1 2 1 2 Which of the following has the correct name for the given formula? (а) Р4О10, tetraphosphorous dodecoxide (Ь) N2 05, dinitrogen pentoxide (с) SF6, hexafluoro sulfide (d) РС1 3, phosphorous tetrachloride (е) CBr4, carbon tetradecabromide Manganese has the highest oxidation state in which of the following? (а) (Ь) MnQ4- (с) МnОз- ( d) (е) Mn02 Mn042- + Mn 3 Which of the following is а salt? (а) LiAlH4 (Ь) (с) CaCl2 Cl2 ( d) CCl4 (е) H 2 S04 Which of the following statements is true? (а) (Ь) (с) ( d) (е) Carbonic acid, Н2 СО3 , is а strong acid. Carbonic acid can Ье obtained Ьу dissolving СО2 in water. Acetic acid, СН3 СООН, is а polyprotic acid. Acetic acid is а strong acid. Hydrochloric acid, HCl, is а polyprotic acid. 6 в 22. How is it possiЫe to deduce the identity of an element :from its electron configuration? (а) (Ь) (с) (d) D 23. Which of the following substances contains fluoride ions? (а) (Ь) (с) (d) (е) D Е 24. 25. The number of filled orbitals coпesponds to the atom's atomic number. If the atom is electrically neutral, the number of electrons coпesponds to the atom's atomic number. Using the periodic tаЫе, the outermost filled orbital indicates the group while the number of occupied orbitals indicates the period. The electron configuration of an element cannot Ье exactlу the same as the electron configuration of any other element or ion. РFз F2 CF4 CaF2 all of the above Which of the following ionic compounds has an incoпect formula? (а) NН4N02 (Ь) СNН4)2СОз (с) LiHS04 (d) LiSOз (е) Са(СlОз)2 Which formula/name pair is incoпect? (а) FeS04 iron(II) sulfate (Ь) Fе2(SОз)з iron(III) sulfite (с) FeS iron(II) sulfide (d) FeS03 iron(II) sulfite (е) Fe2(S04) з iron(III) sulfide 16. D 17. There are __sulfur atoms in 25 molecules of C.JI4S 2• (а) 1.5 х 1025 (Ь) 4.8 х 1025 (с) 3.0 х 1025 (d) 50 (е) 6.02 х 1023 Which of the following best describes а 2 М sucrose solution? (а) (Ь) (с) (d) (е) А 18. There are ____ moles of А1Вr3 in 0.500 L of а 0.300 М solution of А1Вr3. ( а) (Ь) (с) (d) (е) Е 19. 20. 21. Ве В С N О The valence electrons are the electrons that are: (а) (Ь) (с) (d) ( е) Е 0.150 0.300 0.450 0.167 0.500 Which of the following elements has six valence electrons? (а) (Ь) (с) (d) (е) С 1 mole of sucrose dissolved in 2 liters of solution 2 liters of solution that contains 1 mole of sucrose 1 liter of solution that contains 2 moles of water 1 liter of solution that contains 2 moles of sucrose 1 liter of solution that contains 6.02 х 1023 molecules of sucrose closest to the nucleus and therefore unreactive. closest to the nucleus and availaЫe for chemical reactions. farthest from the nucleus and availaЫe for chemical reactions. farthest from the nucleus and therefore unreactive. None of these answers is correct. In а ground-state sodium atom, the ____ suЫevel is partially filled. (а) (Ь) (с) (d) (е) 2s 2р Зр 3d 3s 5