Instructions. 1. Do not open the exam until you are told to start.

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1 Name: Lab Day and Time: Instructions 1. Do not open the exam until you are told to start. 2. This exam is closed note and closed book. You are not allowed to use any outside material while taking this exam. 3. Use the spaces provided to write down your answers. To receive full credit, you must show all work. Do not write answers on any other pieces of paper. If you need more room, write on the back of the exam and be sure to include a note describing where the work is located. 4. When solving numerical problems, make sure you include the proper units in your final answer. 5. If a question asks for a response in sentence or paragraph form, make sure you respond in that format. 6. Useful data for the exam and a periodic table are provided on the last page of the exam. Carefully tear out these sheets if you wish. Page # Points possible Points awarded Attendance 3 EC 1 Total 100 1

2 Multiple Choice Unless otherwise directed, choose the single best answer for each question. Please use the space provided to do your calculations. Make sure your answers have the proper number of significant figures. Each question in the multiple choice section is worth 3 points. 1. How many significant figures should be in the answer to the calculation shown below? a. 2 b. 3 c. 4 d. 5 e = Which of the following contains the largest number of carbon atoms? a. 5CO 2 b. 4C 2 Cl 6 c. C 6 H 12 O 6 d. H 2 CO 3 e. It is impossible to tell. 3. How many significant figures should be in the answer to the calculation shown below? a. 1 b. 2 c. 3 d. 4 e = 4. In an experiment, I determined the mass of a sample of gold to be 2.32 g. If the actual mass is g, calculate the % r.e. associated with my measurement. How many significant digits should be reported in that value? The equations for a.e. and % r.e. are shown below. a. 1 b. 2 c. 3 d. 4 a.e. = A - X a.e. % r.e. = x100% A 2 A = True Value X = My Value

3 5. How many significant figures should be in the answer to the calculation shown below? a. 1 b. 2 c. 3 d. 4 e = 6. How many protons, electrons, and neutrons does 127 I - contain? a. 53, 54, 74 b. 53, 127, 74 c. 53, 74, 53 d. 53, 53, 74 e. 74, 53, Of the following, the smallest and lightest subatomic particle is the. a. neutron d. nucleus b. proton e. alpha particle c. electron 8. How should the number 200,000 be expressed in scientific notation? a x10 5 b x10-5 c. 20x10 4 d. 2.0x10 5 e. 2x Convert mm to kilometers. a km b km c km d km 3

4 10. How many significant figures are in the number ? a. 2 d. 5 b. 3 e. 6 c Convert 21.8 yd 3 to cm 3. (yd = yard) a x10 3 cm 3 b. 2.85x10 7 cm 3 c. 1.99x10 3 cm 3 d. 1.67x10 7 cm When aluminum combines with a non-metal to form an ionic compound, aluminum electrons. a. gains two b. loses two c. gains three d. loses three 13. Convert 2.45x10 4 ML to cl. a cl b. 2.45x10-4 cl c. 2.45x10 3 cl d. 2.45x10 8 cl e. 2.45x10 12 cl 4

5 Use the diagrams below to answer the following two questions about a sample of matter. Assume that the black and grey balls represent different elements and that if they are touching each other they are connected/bonded to each other. A B 14. The matter identified in box A would be best classified as a. a. pure element b. pure compound c. homogeneous mixture d. heterogeneous mixture e. both a pure element and a pure compound 15. The transition from box A to box B best represents what kind of change? a. A chemical change. b. A physical change. c. Both a chemical and a physical change. 16. The scientific method involves: I) observations III) elementation II) theories IV) experimentation a. I, II, III d. II, III, IV b. I, III e. I, II, III, IV c. I, II, IV 17. How should x10 9 be expressed in the proper form of scientific notation? a x10 9 d x10 7 b. 6.10x10 12 c. 6.1x

6 18. If gasoline costs 98.5 cents per liter in Nebraska, what is the cost (in dollars) for 2.00 gallons of gasoline? a. $7.46 b. $7.88 c. $2.08 d. $8.32 e. none of the above 19. An element in the lower left corner of the periodic table. a. is either a metal or a metalloid b. is definitely a metal c. is either a metalloid or a non-metal d. is definitely a non-metal e. is definitely a metalloid 20. An element has a mass number of 60 and contains 24 electrons as a 3+ ion. What is the identity of the element? a. Sc b. Cr c. Co d. Kr 21. How many significant figures should be in the answer to the calculation shown below? x x10 = x10 a. 1 b. 2 c. 3 d. 4 e Which quantity of subatomic particles determines the identity of an atom? a. The number of protons. b. The number of electrons. c. The number of neutrons. d. The number of nuclei. 6

7 23. Fill in the missing information into the table. (10 points) Element Name Element Symbol W Potassium Cl Silver Mo 24. For the following questions fill in the blank with a word, phrase, or number that best completes the sentence. Put your answer in the column on the right. (8 points) a. The volume of a sample of Pepsi TM is 340 ml. The absolute uncertainty of the measurement. b. The chemical formula for the ionic compound that forms between vanadium (V) and phosphorus is. Assume that vanadium forms a 2+ ion. c. The smallest halogen is. (give the chemical symbol) 25. On the left hand side of the arrow below, draw a picture of the sulfur (S) atom. Assume the sulfur atom has 17 neutrons. On the right hand side of the arrow, draw a picture of the ion that sulfur forms. In your diagrams, include the location and number of the protons, neutrons, and electrons. Label the nucleus and make sure the relative sizes of the atom and ion are accurate. Under the ion, state whether it is a cation or anion. (5 points) 7

8 26. A graduated cylinder contains water and an irregularly shaped object with a combined volume of in 3. a. When the object is removed from the graduated cylinder, what happens to the level of the water? (1 point) b. If the object has a mass of pounds, what is the mass in μg? Put your answer in scientific notation. (3 points) c. If the object has a density of 2.631x10-2 μg/nl, what is the volume of the water in the graduated cylinder when the object is removed? Report your answer in cubic inches and assume no water is lost when the object is removed. You must show all your work and use multi-step dimensional analysis to receive full credit. (4 points) 27. This problem is extra credit. What is the temperature indicated by the linear scale shown on the right? (1 point) 8

9 Conversion Factors, Constants, and Periodic Table 1 m = yards 1 inch = 2.54 centimeters (exact) 12 inches = 1 foot (exact) 1 gallon = liters 1 mile = kilometers 1 pound = grams 1 ton = 2000 pounds (exact) 1 dollar = 100 cents (or pennies) (exact) 1 H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc (98) 44 Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po (209) 85 At (210) 86 Rn (222) 87 Fr (223) 88 Ra Ac Rf (261) 105 Db (262) 106 Sg (263) 107 Bh (262) 108 Hs (265) 109 Mt (266) 110 Uun (269) 111 Uuu (272) 112 Uub (277) Ce Pr Nd Pm (145) 62 Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U Np (237) 94 Pu (244) 95 Am (243) 96 Cm (247) 97 Bk (247) 98 Cf (251) 99 Es (252) 100 Fm (257) 101 Md (258) 102 No (259) 103 Lr (260) 9