A. 2.5 x 10 2 ml B. 4 x 10-3 ml C x 10 2 ml D ml E. the volume of the ball cannot be measured with the information given.

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1 hemistry 11 Spring 2011 Examination #1 ANSWER KEY For the first portion of this exam, select the best answer choice for the questions below and mark the answers on your scantron. Then answer the free response questions that follow (100 pts. total; multiple choice 2 pts. each). 1. Which of the following has the largest atomic radius? A. Iodine B. Magnesium. Barium D. hlorine E. Nitrogen 2. I threw a plastic ball in the pool for my dog to fetch. The mass of the ball is 125 grams. What must the volume be to have a density of g/ml? A. 2.5 x 10 2 ml B. 4 x 10-3 ml x 10 2 ml D ml E. the volume of the ball cannot be measured with the information given. 3. After throwing the ball (from question 2) in the pool for my dog, the ball sprung a leak and began to fill with water. ow many ml of water can the ball absorb before the ball sinks? A. anything less than ml water B. anything greater than 1.00 ml water. anything less than 125 ml water D. anything greater than 125 ml water E. anything less than 1.00 ml water 4. Identify the best answer to the following calculation: ( ) A B D E

2 5. The local TV weather report gives the high temperature for the day as 76 o F. What is this temperature in o? A B D. 170 E Which of these measurements was made with the most accurate measuring device? A m B m. 8.2 m D. 8 m E m 7. An intensive care patient is receiving an antibiotic IV at the rate of 50. ml/h. The IV solution contains 1.5 g of the antibiotic in ml. alculate the mg/min of the drip. A mg/min B mg/min mg/min D. 75 mg/min E. 1.3 mg/min 8. Determine the number of protons, neutrons, and electrons present in 94 Mo 7+. A. 42 protons; 94 neutrons; 35 electrons B. 42 protons; 52 neutrons; 35 electrons. 42 protons; 52 neutrons; 49 electrons D. 94 protons; 1 neutron; 35 electrons E. 94 protons; 2 neutrons; 101 electrons 9. Determine the expected electronic configuration for Fr + (atomic # 87) A. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 4d 10 4p 6 5s 2 5d 10 5p 6 6s 2 6f 14 6d 10 6p 4 B. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 6p 6. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 6p 6 7s 1 D. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 10 4p 6 5s 2 4d 10 5p 6 6s 2 4f 14 5d 10 6p 5 E. 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 4d 10 4p 6 5s 2 5d 10 5p 6 6s 2 6f 14 6d 10 6p 6 2

3 10. Given the calculation (9.60 x ) / (5.0 x ), what is the answer reported to the correct number of significant figures? A x B x x D. 1.9 x E. 1.9 x The specific heat of liquid bromine is J/g K. ow much heat (in cal) is required to raise the temperature of 10.0 ml of bromine from 25.0 º to 27.3 º? The density of liquid bromine is 3.12 g/ml. A calories B calories. 464 calories D. 460 calories E calories 12. Which of the following is a homogeneous mixture? A. helium gas used to fill a balloon B. chicken noodle soup. sand in water D. air E. solid sodium chloride 13. Arrange the following in order of increasing electronegativity: s, F, As, l A. As < l < s < F B. l < As < F < s. As < F < s < l D. l < s < F < As E. s < As < l < F 14. Express in exponential notation A x 10 3 B x x 10 3 D x 10 4 E x

4 15. Which of the following is a chemical change? A. the freezing of water to form ice B. hammering zinc into a thin film. the sublimation of dry ice D. the boiling of water to form steam E. the reaction of chlorine gas and sodium to form sodium chloride 16. An object with a mass of 7.5 g raises the level of water in a 50.0 ml graduated cylinder from 25.1 ml to 30.1 ml. What is the density of the object? A g/ml B. 1.5 g/ml. 2 g/ml D. 4 g/ml E. None of the above 17. Which ion is not correctly paired with its name? A. P -3 3, phosphate B. N - 3, nitrate. -, hydroxide D. -2 3, carbonate E. S -2 3, sulfite 18. What mass of lead (density 11.4 g/cm 3 ) would have an identical volume to 15.0 g of mercury (density 13.6 g/cm 3 ) A g B. 13 g g D g E. none of the above 19. Which of the following is characteristic of most metals? A. good conductor of heat and electricity B. generally possess high melting point. can be hammered flat into sheets D. readily oxidize to form cations E. all of the above 4

5 20. Aluminum reacts with a certain element to form a compound with the general formula AlX. What would the most likely formula be for the compound formed between sodium and element X? A. Na 2 X B. NaX 2. Na 2 X 3 D. Na 3 X E. NaX 21. List the following in order of increasing ionization energy:, Mg, Rb, S, Si A. Si < < Mg < Rb < S B. Si < S < Rb < Mg <. Mg < < Rb < S < Si D. Rb < Mg < Si < S < E. S < Si < Mg < < Rb For Questions 22 25, reference the structure of Folic acid also known as Vitamin B below. Folic acid is essential for DNA synthesis as well as during rapid cell division and growth. N N N N N N N A 22. Based on your knowledge of VSEPR, which of the following geometries is NT present in Folic acid? A. trigonal planar B. tetrahedral. bent D. trigonal pyramidal E. All of the above are present in Folic acid. 5

6 23. Select A for True R B for False regarding the following statement: Folic acid does possess resonance. A 24. Select A for True R B for False regarding the following statement: Folic acid is predominantly polar. A 25. What is the number of lone pairs around the nitrogen labeled A? A. 0 B D. 3 E (22 pts. total; 2 pts. each) Write the name/chemical formula for each of the following listed below: A. iron(ii) oxide Fe B. ZnS 4 zinc sulfate. barium acetate Ba( ) 2 D. sulfur trioxide S 3 E. ui 2 copper(ii) iodide F. lead(ii) phosphate Pb 3 (P 4 ) 2 G. calcium nitrite a(n 2 ) 2. K 2 potassium oxide I. l 4 carbon tetrachloride J. Sr 3 strontium carbonate K. Ammonium cyanide N 4 N 6

7 27. (28 pts. total; 7 pts. each) onsider each of the following ions/molecules shown below and write your final structures in the boxes provided: A. Beginning with the best Lewis dot structure, use VSEPR theory to draw each of the listed species, including resonance where appropriate. Don t forget to include lone pairs! B. Describe the geometry about EA central atom. Include both electronic and molecular geometries.. Give the approximate bond angle(s) around each central atom. D. Determine whether the overall species is polar or nonpolar. ***NTE: Terminal atoms are assumed to have an octet of electrons (excluding hydrogen) omitted for the sake of clarity! N N N N N N Structure #1 electronic geometry: trigonal planar Structure #2 electronic geometry: linear molecular geometry: approx. bond angle: bent 120 molecular geometry: linear approx. bond angle: 180 polar or nonpolar? polar polar or nonpolar? polar R Structure #3 Structure #4 electronic geometry: tetrahedral (all) electronic geometry: 1: tetrahedral 2: trigonal planar molecular geometry: tetrahedral molecular geometry: 1: tetrahedral () bent 2: trigonal planar approx. bond angle: (all) approx. bond angle: and 120 polar or nonpolar? polar polar or nonpolar? polar (ionic) - 7

8 BNUS! (5 pts. total) You give your home health patient an unopened 500. ml bottle of guaifenesin (used to relieve chest congestion) and tell them to take 2 teaspoons 4 times a day as ordered. They ask you how long the bottle will last. What is your answer? Your final answer should be rounded to 3 significant figures. (1 tsp = 5.00 ml) # of teaspoons per day = 8 tsp = ml in one day Therefore, 500. ml/40.00 ml/day = 12.5 days 8