NAME Section number. Dr. Rick Fletcher. Clearly print your name in the name section of the Scantron answer sheet.

Transcription

1 NAME Section number Dr. Rick Fletcher Exam 1 Chemistry 101 September 24, 2007 Clearly print your name in the name section of the Scantron answer sheet. Clearly place your student ID number in the SUBJECT section of the Scantron sheet. Maintain appropriate security over your exam. Do not let others see your answers. There is only one most correct response to each of the multiple choice questions. Choose the best answer. Each of the twenty-five questions is worth 4 points. Since the Scantron sheets will not be returned to you, please work through the entire exam and circle the best answer on this exam. Mark this exam as you work the problems then transfer the responses to the Scantron sheet all at one time. This is the best way to reduce errors. Use pencil on the Scantron sheets and make certain to fully erase any changes you make. Use this exam to check your answers on the key that will be posted online cm = 1 in 454 g = 1 lb 946 ml = 1 qt 5280 ft = 1 mile 16 oz = 1 lb 4 qt = 1 gal heat = (sp. Ht.) X (mass) X (ΔTemp) T (K) = T ( C) T( F) = (1.8 X T( C)) cal = J Page 1

2 1. In planning a party, you have $50 to purchase the beef required to feed everyone. If the cost of beef is $2.49 per pound, how much beef can you purchase? A) 44 kg B) 125 lbs C) 20 kg D) 9.1 kg 2. From the results of his gold foil experiment, Rutherford concluded that A) atoms contain roughly equal numbers of neutrons and protons. B) alpha particles are helium nuclei. C) electrons have a charge of -1.6 x C. D) atoms are composed of a small, dense nucleus surrounded by a cloud of electrons. 3. A nonmetal atom that gains an electron is known as a(n) A) cation. B) sodium ion. C) anion. D) onion. 4. Which one of the following substances is not an element? A) aluminum B) argon C) salt D) carbon 5. Sitting on a bench top are several samples: lithium metal (d = 0.53 g/ml), gold (d = 19.3 g/ml), aluminum (d = 2.70 g/ml), and lead (d = 11.3 g/ml). If all of the samples have the same volume, which one possesses the greatest mass? A) lead B) aluminum C) lithium D) gold 6. Which one of the following is not one of the four postulates of the atomic theory? A) chemical reactions are merely rearrangements of the atoms. B) chemical compounds are composed of atoms of different elements C) atoms are divisible D) atoms of the same element have the same properties Page 2

3 7. Which one of the following prefixes is used in the metric system? A) meta- B) hepta- C) penta- D) deci- 8. How many atoms are in one molecule of capsaicin, C 18 H 27 NO 3? A) 49 B) 48 C) Not enough info D) 4 9. What is the identity of X? A) copper(cu) B) molybdenum (Mo) C) technetium (Tc) D) einsteinium (Es) 10. A textbook has mass of 2.33 lbs. What is the mass of the text in units of milligrams? 1 lb. = 454 g A) 1.06x10 6 mg B) 1.06 mg C) 5.13 mg D) 1.06x10 3 mg 11. A laser beam travels a distance of m in seconds. Which one of the following is the best expression (scientific notation) for the velocity of the beam? A) 3.84x10-9 m/sec B) 3.8x10-9 m/sec C) 3x10 8 m/sec D) 2.61x10 8 m/sec 12. Of the three states of matter, which one normally possesses the highest density? A) gas B) solid C) not enough information D) liquid Page 3

4 13. Five students obtain the following grades on an exam. What is the average score on this exam for these students? (88, 69, 81, 92, 79) A) 82 B) C) 81.8 D) Which one of the following prefixes is not used in the metric system? A) mega- B) nano- C) kilo- D) tetra- 15. How many significant figures does possess? A) 6 B) 3 C) 1 D) The melting point for a form of coal is 669 K. What is its melting point in o C? A) 396 B) 376 C) 942 D) When white, crystalline sugar is heated, it decomposes into a colorless liquid and a black solid. This evidence suggests that sugar is A) not very dense. B) an element. C) a mixture. D) a compound. 18. A large glass jar contains 1248 jellybeans, each of which occupies a volume of 435 mm 3. What is the volume of the jar in units of liters? A) 28.7 L B) L C) 5.43 L D) 2.87 L Page 4

5 19. A beaker contains 605 g of ethanol at 2.0 o C. A 300-g sample of aluminum (spht = J/g o C) initially at 340 K is then submerged in the ethanol. If the final temperature of the system is 285 K, what is the quantity of heat transferred? A) 2700 J B) J C) 5400 J D) not enough information, need specific heat of ethanol 20. Two atoms with the same number of protons, but a different number of neutrons, are known as A) atoms. B) nucleons. C) isotopes. D) elements. 21. Which one of the following substances in not a pure substance? A) hydrogen gas B) carbon monoxide C) salad dressing D) copper 22. A 10-g sample of an unknown metal displaces 0.88 ml of water. Determine the identity of the metal given the following: Li (d = 0.53 g/ml), Au (d = 19.3 g/ml), Al (d = 2.70 g/ml), and Pb (d = 11.3 g/ml). A) lead B) aluminum C) lithium D) gold 23. A change, whether physical or chemical, that absorbs heat from the surrounding is A) an exothermic change. B) an endothermic change. C) an exotic change. D) an ectodermic change. Page 5

6 24. The smallest fundamental particle of an element that has the properties of that element is the A) neutron. B) proton. C) atom. D) electron. 25. Which of the following depicts the number of subatomic particles in the ion 202 Hg 2+? A) 78 protons, 80 electrons, 158 neutrons B) 80 protons, 82 electrons, 128 neutrons C) 80 protons, 78 electrons, 122 neutrons D) 202 protons, 200 electrons, 80 neutrons 26. Please indicate you are taking Version A of this exam by marking the A response on QUESTION 26 ON THE REVERSE SIDE OF THE SCANTRON SHEET. Failure to do this will invalidate your responses. Page 6