Copy of Exam 1 for CHM 101A Lecture Section

CHM 101A Version 1 1 P. Marks 2008 Name:__________________________ Lab TA Name:_________________________ Lab Section Code: ________________________ CHM 101A Exam 1 September 16, 2008 VERSION 1 100 pts 1. You are responsible for the information on this page. Please read it carefully. 2. On the exam booklet, PRINT your name, lab TA name, and lab section number. 3. On the scantron, print and code both your name and 10-digit affiliate ID on the scantron sheet. The affiliate ID is the second sequence of numbers on your University ID card. 4. Use only a #2 pencil. 5. Do all calculations on the exam pages. Do not make any unnecessary marks on the answer sheet. 6. This exam consists of 30 multiple choice questions worth 3.333 points each and a periodic table. Make sure you have them all. 7. Choose the best answer to each of the questions and answer it on the computer-graded answer sheet. Also circle your choice in the exam booklet for your records. Read all responses before making a selection. 8. When you are finished, turn in both your exam booklet and your scantron. Exam booklets will be returned in lab. Scantrons will not be returned. Potentially useful information: 1 inch = 2.54 cm 1 lb = 453.6 g 1 quart = 0.9464 L 4 quart = 1 gallon 32 fluid ounces = 1 quart 1 mL = 1 cm 3 C 5 9 32 ºFº += K = ºC + 273.15 CHM 101A Version 1 2 P. Marks 2008 1. Which of the following describes a chemical change? A. Deposition of a gaseous metal B. Evaporation of water C. Cu(s) ? Cu(l) D. Burning hydrogen E. All of these are chemical changes. 2. Which of these images is a representation a pure substance that is an element? I. II. III. IV. V. A. I and III D. I and V B. II E. V C. III 3. Which of the following represents a pure compound? A. Salt water B. NaNO 3 (s) C. C 12 H 22 O 11 (aq) D. N 2 (g) E. All of the above 4. The length of each side of a metal cube is 2.0 cm. The density of the substance that makes up the cube is 0.942 g/mL. What is the mass of the cube? A. 3.8 g B. 1.9 g C. 7.5 g D. 0.47 g E. 0.12 g 5. For a given molecular substance, the gas state is less dense than the liquid state because A. each molecule in the gas state is greater in mass than those in the liquid state. B. each molecule in the gas state is lower in mass than those in the liquid state. C. there is more empty space between molecules in the gas state than in the liquid state. D. there is more empty space between molecules in the liquid sate than in the gas state. E. the gas-state molecules are smaller in size than the liquid-state molecules. 2.0 cm CHM 101A Version 1 3 P. Marks 2008 6. Convert 1.2 ×10 ?4 m to mm. A. 1.2×10 ?2 mm B. 1.2×10 ?3 mm C. 1.2×10 ?7 mm D. 12 mm E. 0.12 mm 7. The diameter of a sulfur atom is 1.03×10 ?10 m. What is this diameter in units of picometers, pm? A. 1.03 pm B. 0.103 pm C. 103 pm D. 1.03×10 ?22 pm E. 1.03×10 ?12 pm 8. What is the density of a substance with a mass of 4.25×10 ?3 g and a volume of 7.3×10 ?4 cm 3 . A. 1.7×10 ?7 g/cm 3 B. 0.17 g/cm 3 C. 5.8×10 ?8 g/cm 3 D. 3.1 g/cm 3 E. 5.8 g/cm 3 9. Which of the following element names and formulas is paired correctly? A. Copper, C B. Fluorine, F C. Potassium, P D. Sodium, S E. Zinc, Z 10. Which of the following statements about energy is FALSE? A. Heat is a form of energy. B. Chemical changes are accompanied by energy changes. C. Physical changes are accompanied by energy changes. D. Kinetic energy increases as temperature increases. E. Energy has mass. 11. How many significant figures should be in the result of the calculation which converts 25.00 mg to grams? A. 2 B. 3 C. 4 D. 5 E. 6 CHM 101A Version 1 4 P. Marks 2008 12. Which of the following is a formula that best matches what is shown in the molecular-level diagram? A. H 2 O(l) B. I 2 (s) C. N 2 (g) D. NaCl(s) E. O 2 (g) 13. The lowest possible temperature is the temperature at which there is no molecular motion and therefore no kinetic energy. What is the lowest possible temperature in ?C units? A. 0.00?C B. ?273.15?C C. 273.15?C D. ?100?C E. ?723?C 14. Which of these elements is a halogen? A. helium D. oxygen B. bromine E. uranium C. lithium 15. An isotope with 15 protons and 16 neutrons has which of the following symbols? A. 16 15 P B. 31 15 P C. 31 16 S D. 15 16 S E. 31 16 Ga 16. In Rutherford?s gold foil experiment, Rutherford observed that some of the alpha particles aimed at a thin layer of gold foil were deflected, while most went straight through. This unexpected result showed that: A. the plum pudding model of the atom is better than the nuclear model of the atom. B. neutrons exist. C. electrons have a negative charge. D. the gold atoms have a dense positively charged nucleus. E. the gold atoms have a dense negatively charged nucleus. 17. Calculate the relative atomic mass of Laurium, a fictional element, if it has two isotopes with the following abundance and masses: 32 L 31.89 amu 64.88% 34 L 33.84 amu 35.12% A. 35.22 amu B. 32.57 amu C. 32.87 amu D. 33.84 amu E. 65.74 amu CHM 101A Version 1 5 P. Marks 2008 18. How many electrons does a Cr 3+ ion have? A. 24 B. 27 C. 21 D. 52 E. 49 19. Naturally occurring rubidium is comprised of two isotopes: rubidium-85 and rubidium-87. Which of the following statements can be said about their natural relative abundance? (Refer to the periodic table.) A. Rubidium-85 is present is the largest percent abundance. B. Rubidium-87 is present is the largest percent abundance. C. The isotopes are present in the same percentages (50% and 50%) D. There must be a third naturally-occurring isotope with a mass number less than 85. E. There must be a third naturally-occurring isotope with a mass number greater than 87. 20. Which of the following statements about subatomic particles is CORRECT? A. A neutron has a negative charge. B. A neutron and an electron have approximately the same mass. C. A proton and a neutron have the same charge. D. The mass of a proton is about 2000 times greater than the mass of an electron. E. Electrons are contained in the nucleus of an atom. 21. Which of the following symbols represents a chloride ion? A. Cl B. Cl 2 C. Cl 2? D. Cl ? E. Cl 2 2? 22. Which of the following elements occurs naturally as diatomic molecules? A. sulfur B. nitrogen C. helium D. calcium E. carbon 23. The name of the oxoanion of chlorine with a 1? charge shown in the figure is: A. chlorooxate ion B. chloride ion C. chlorite ion D. chlorate ion E. chlorine trioxide ion 24. Which of the following is the formula for a molecular compound? A. SO 3 2? B. H 2 O C. NaCl D. NH 4 Cl E. NaNO 3 O Cl CHM 101A Version 1 6 P. Marks 2008 25. Which of the following is NOT an electrolyte? A. Mg(NO 3 ) 2 , a soluble ionic compound B. Tartaric acid C. NaOH, a soluble base D. Sucrose, a molecular compound. E. NaCl (table salt) 26. What is the formula for a compound composed of potassium ions and phosphate ions? A. KPO 4 B. K 2 PO 4 C. K 2 (PO 4 ) 3 D. K 3 (PO 4 ) 2 E. K 3 PO 4 27. What is the formula for the compound manganese(IV) oxide? A. MnO B. Mn 4 O C. MnO 2 D. MnO 4 E. Mn 2 O 28. The compound SO 2 is a colorless gas with a boiling of ?10?C. Name this molecular compound. A. sulfite B. sulfate C. sulfur(IV) oxide D. sulfur(II) oxide E. sulfur dioxide 29. What is the correct name for Ca(NO 3 ) 2 ? A. calcium nitrite B. calcium nitrate C. calcium dinitrate D. calcium(II) nitrite E. calcium nitride 30. Which of the following acids is named incorrectly? A. HBr(aq), bromic acid B. H 2 S(aq), hydrosulfuric acid C. H 2 SO 4 (aq), sulfuric acid D. H 3 PO 4 (aq), phosphoric acid E. HNO 3 (aq), nitric acid marks Microsoft Word - CHM101A Exam 1 v1.doc