Name_________________ Unit 8 Atomic Theory and Periodicity -1- Name_________________ Chemistry Unit 8: Atomic Theory and Bonding Assignment WB Page Number Podcast 8.1 Video Clip + Discussion with your teacher: Mindwalk Worksheet A Podcast 8.2 Black Box Lab Demo: Spectral Tubes + Discussion with Teacher Demo: And Then There Was Light + Discussion with your teacher Take Home Lab: Let there be Light Lab: Flame Tests Worksheet B Podcast 8.3 (CB 15-27)—This is a long one Lab-Activity: Periodic Trends Worksheet C Worksheet D Lab: Model Building Podcast 8.4 (CB 29-35) Worksheet E Molecular Modeling Computer Activity Worksheet F Unit 8 Exam Online + CB Pages In Class Can Only be done in Class Online + CB Pages Teacher Handout In Class X X In Class X Pg 7 Pg 8-9 Pg 16-17 Online + CB Pages Pg 11-12 Pg 18 Pg 19-20 Teacher Handout Online and CB Pages Pg 21 Online: See Teacher Pg 22 In Class -2- X Done? Name_________________ Take Home Lab Parent/Student Experiment Title: And Then There Was Light.... Subject/Concept: Chemistry - Photon Emission Purpose: The purpose of this activity is to observe the emission of photons in your own home! Don’t worry, this happens all the time! Materials: several commercial bandage strips (3” x .75” with pull-apart packaging - no strings!) CURAD™, KING SOOPERS™, OR SAFEWAY™ brands work well regular Wintergreen LifeSavers™ candies or Wintergreen LifeSavers™ Holes Procedure: In an absolutely pitch dark room (bathrooms often work), do the following: Pull apart the bandage strip packaging with very quick pulls of about a half inch or so. You should see the emission of a small purple photon! While your partner looks on, crush the wintergreen candy between your teeth and your partner will see the emission of a small photon! Questions: 1. What is the source of the emitted photon? 2. Make a drawing of the Rutherford-Bohr model of an atom showing the movement of an electron during the process of light emission. For Credit: To receive credit, complete the questions for this lab on a separate piece of paper. Also, your parent or guardian must write a short note confirming that you performed the experiment for them and explained the results to their satisfaction using the concept of photon emission and electron energy levels. Attach your note to the back of this sheet. -3- Name_________________ Flame Test Lab Chemists began studying colored flames in the 18th century and soon used "flame tests" to distinguish between some elements. Different elements burn with different colored flames. Although some of the flames you will be seeing will appear similar in color, their light can be resolved (separated) with a prism into distinctly different bands of colors on the electromagnetic spectrum (ROYGBIV). These bands of colors are called atomic line spectra, and they are UNIQUE to each element. Niels Bohr studied the line spectrum for hydrogen, and wondered what the specific line spectrum had to do with the structure of the atom. He postulated that an electron can have only specific energy values in an atom, which are called energy levels. Bohr believed that the energy levels for electrons were quantized, meaning that only certain, specific energy levels were possible. How does an electron move between energy levels? By gaining the right amount of energy, an electron can move, or undergo a transition, from one energy level to the next. We can explain the emission of the light by atoms to give the line spectrum like this: 1. An electron in a high energy level (excited state) undergoes a transition to a low energy level (ground state). 2. In this process, the electron loses energy, which is emitted as a photon (a particle which behaves like a wave) 3. The energy difference between the high energy level and the low energy level is related to the frequency (color) of the emitted light. Pre-lab questions: 1. Bohr's important discovery was that energy levels of electrons are quantized (only existing in certain, specific levels). In what year was this discovery made? _____________ 2. What happens to an electron when energy is added? 3. What is released when an electron loses energy? 4. What determines the frequency (color) of photons? 5. Why do you think the frequencies (color) for a specific element is always the same? Procedure: In this lab, you will be observing the colors of the flames for 7 different elements: lithium, sodium, potassium, calcium, strontium, barium, and copper. Each element is dissolved in a solution of its chloride salt. There is a different solution at each lab station. You will go around to all 7, perform the flame test, and make CAREFUL observations of the colors. You will then be given an unknown solution, for -4- Name_________________ which you will have to use your notes below to determine which unknown you were given. Post- Lab Questions: 1. If you had 2 colors that seemed identical, how could you tell them apart more accurately? 2. Albert Einstein determined this equation: energy (in joules) of a photon is equal to Planck's constant times the frequency of the light: E = h • • Frequency () has units of 1/sec (which is a Hertz, or Hz) • Planck's constant (h) = 6.63 x 10-34 J·sec a) If the frequency of a red spectrum line is at 1.60 x 1014 Hz, how much energy does each photon of this light have? b) If the frequency of a violet spectrum line is at 2.50 x 1014 Hz, how much energy does each photon of this light have? c) On the far ends of the visible spectrum of light, there exists ultraviolet (UV) radiation and infrared (IR) radiation. - UV radiation is dangerous. UV radiation is located just past violet on the spectrum. IR radiation is harmless. It is located just past red on the spectrum. Based on what you calculated in parts a & b, explain -why- UV is more dangerous than IR: -5- Name_________________ Lab: A Black Box Overview: As humans, we rely on our senses to tell us about the world around us. Does that mean we can only understand those things we can see, feel, hear, taste, or touch? Of course not. Sometimes we can sense things indirectly. For example, let's say you're alone in the house, and leave a juicy cheeseburger on the table for a few minutes while you answer the phone. You return five minutes later and find that the cheeseburger is gone. You also notice your dog contentedly sitting under the table. Perhaps it looks at you and burps. It's pretty obvious that the dog must have eaten the cheeseburger since cheeseburgers don't walk away by themselves. You didn't sense the event directly, but based on everything you've experienced about the world before allows you to logically figure out what must have happened. Scientists must also use indirect observations to answer many questions about things that are impossible or difficult to observe directly. This is certainly true about our understanding of atoms. In science, the term "black box" is used to describe something when we understand how it behaves (and can even make predictions about what it will do in a given situation), but are not able to see exactly what is going on inside it to make it behave the way it does. Atoms are a great example of a scientific "black box." We are doing this lab because, before we begin to study atoms, it's a good idea to experience what it's like to investigate a "black box." The 4 boxes you'll be using are literally boxes, but you'll follow the same basic methods that scientists use to study anything that cannot be directly observed. Here's how you to proceed with this lab: 1. Make and record as many observations about the box as you can without removing any rods or looking inside. It is helpful to team up with another lab pair and their box so that you can compare notes. Draw a sketch of what you think the inside of the box is like based on these observations. 2. Decide which rod you would like to remove, and write down a prediction of what will happen when you do this. Try it, and record what happens. 3. You may then use another lab pair's box to remove a second rod. Record what happens. Remember that each time you remove a rod you are possible changing the contents of the box in a way that cannot be reversed. Take your time, and only remove one rod at a time. -6- Name_________________ 4. Draw a final sketch of what you think the inside of the box looked like before you removed any rods. Continue with the next box until you have developed models for all four boxes. Discussion Notes: a) Discuss how this activity relates to what scientists do in real-life, giving examples. b) Discuss your confidence in the models of the boxes you have developed. Would you be willing to publish the results? Do you think it is possible that your model will change if new information is discovered? How is this similar to the model of the atom that scientists have developed? -7- Name_________________ Model Building Using Styrofoam balls and toothpicks, build each shaped structure that is taught in the podcasts. Credit is earned when you show these to your teacher and answer the following questions: 1. What is VSEPR? 2. What is the pattern on angles for those atoms with 4 shells (or clouds) as you go from 4 atoms connected to 2 atoms connected? 3. Why do you think this pattern occurs? 4. How does the shape of the molecule affect the polarity of the molecule? 5. Using your models, explain to your teacher why water is a polar molecule. 6. Using your models, explain why carbon tetrachloride is a non-polar molecule. -8- Name_________________ Molecular Shapes “clouds” 2 Linear Diatomic Polarity depends upon electronegativity difference Polar if >0.5 Nonpolar if <0.5 Linear Triatomic, Usually nonpolar CO2, HCN 3 Trigonal Planar: BF3, SO32-, NO3120˚ Usually nonpolar In molecules where the outside molecules are different, shapes that tend to be nonpolar usually become polar. Remember to count the number of “clouds” of electrons, not the actual number of electrons. A double or triple bond counts as one effective pair. Bent, 12O˚ Usually polar NO2- Also: If there ever is a two molecule atom (diatomic) that molecule’s polarity depends upon the electronegativity difference of the atoms 4 Tetrahedral; 109˚: Usually nonpolar CH4, CF4 Pyrimidal: 107˚ Usually polar: NH3, PCl3 Bent: 104.5˚ Usually polar: H2O, OF2 Molecular Shapes “clouds” 2 Linear Diatomic Polarity depends upon electronegativity difference Polar if >0.5 Nonpolar if <0.5 Linear Triatomic, Usually nonpolar CO2, HCN 3 Trigonal Planar: BF3, SO32-, NO3120˚ Usually nonpolar Remember to count the number of “clouds” of electrons, not the actual number of electrons. A double or triple bond counts as one effective pair. Bent, 12O˚ Usually polar NO2- 4 Tetrahedral; 109˚: Usually nonpolar CH4, CF4 In molecules where the outside molecules are different, shapes that tend to be nonpolar usually become polar. Pyrimidal: 107˚ Usually polar: NH3, PCl3 -9- Bent: 104.5˚ Usually polar: H2O, OF2 Also: If there ever is a two molecule atom (diatomic) that molecule’s polarity depends upon the electronegativity difference of the atoms Name_________________ Periodicity Graphs Directions: Construct three computerized graphs using the data from the table below. Graph 1: electronegativity (on y-axis) versus atomic number (on x-axis) Graph 2: first ionization energy (on y-axis) versus atomic number (on x-axis) Graph 3: atomic radius (on y-axis) versus atomic number (on x-axis) On each graph, use a connected line between data points. Also, the title of each graph must also include your initials. For each graph, include a short explanation which: (A) defines the property on the y-axis, (B) discusses the general trend of the property across the rows of the periodic table (Periodic Trends), and (C) discusses the general trend of the property down the columns of the periodic table (Group Trends). More information on this subject can be found in Chapter 13 of your text book. Periodic Trends - Element Data Table Element Atomic Number Electronegativity First Ionization Atomic Radius Symbol (use on x-axis) (no units) Energy (kJ/mole) (picometers) ----------------------------------------------------------------------------------------------------------------------------------H 1 2.1 1312 He 2 - -(skip) 2371 Li 3 1.0 520 -----------------------------------------------------------------Be 4 1.5 900 B 5 2.0 800 C 6 2.5 1086 -----------------------------------------------------------------N 7 3.0 1402 O 8 3.5 1314 F 9 4.0 1681 -----------------------------------------------------------------Ne 10 - -(skip) 2080 Na 11 0.9 495.8 Mg 12 1.2 737.6 -----------------------------------------------------------------Al 13 1.5 577.4 Si 14 1.8 786.2 P 15 2.1 1012 -----------------------------------------------------------------S 16 2.5 999.6 Cl 17 3.0 1255 Ar 18 - -(skip) 1520 -----------------------------------------------------------------K 19 0.8 418.8 Ca 20 1.0 589.5 ------------------------------------------------------------------ - 10 - 37 50 140 90 80 77 71 66 64 70 157 136 143 118 109 103 91 94 196 174 Name_________________ Periodic Trends Graph - 11 - Name_________________ WS A: History of the atom and Electron Configurations 1. Identify the two particles found in the nucleus of an atom. 2. What is an electron? 3. Identify the scientists (Thompson, Bohr, Rutherford, or Newton) who proposed each of the models illustrated below: 4. What specific evidence (from the gold foil experiment) led Rutherford to come to the each of the following conclusions? a. The nucleus occupies very little space in the atom. b. An atom is made of mostly empty space. c. The nucleus is positively charged. - 12 - Name_________________ 5. For each of the elements listed below, complete the following: a. long hand electron configuration b. orbital diagram (boxes with arrows) c. short hand electron configuration (begins with a noble gas) 1. Li 2. Na 3. K 4. B 5. Al 6. Ne 7. Ar 8. Mg - 13 - Name_________________ 9. P 10. Ni 11. Zn 12. Br 13. H 14. He 15. Ca2+ 16. N3- 17. Na1+ - 14 - Name_________________ WS B: Light and Light Equations 1. If an electron goes from level 4 to level 2 what happens? Be specific. 2. Fill in the following table Violet Energy (Joules) 6.3 x 10-19 J Blue Wavelength-λ (meters) Green Yel Frequency –ν (s-1) 2.4 x 10-7 m 100 s-1 1.5 x 10-14 J 10 Orange 2.2 x 1013 s-1 525 nm - 15 - Red Color of Light/type of electromagnetic radiation Name_________________ The diagram above represents the spectra of three different elements. Explain the following: a. Why are they different b. Why are they not a continuous series of colors (ROYGBIV)? c. How are these used in the field of Astronomy? - 16 - Name_________________ Part C: Periodicity 1. List the following atoms in order of increasing electronegativity: a. Cr, Ni, Ga, K b. P, As, F, Hg, Fr 2. List the following atoms in order of increasing atomic radius: a. Cr, Ni, Kr, Ga, K b. P, As, F, Hg, Fr 3. List the following atoms in order of increasing ionization energy: a. Cr, Ni, Kr, Ga, K b. P, As, F, Hg, Fr 4. Why are alkali metals stored in kerosene or mineral oil? Why are they not allowed to sit out in the air? 5. The Mg+2, and the Na+1 ions each have ten electrons surrounding the nucleus. Which ion would you expect to have the smaller radius? - 17 - Name_________________ Worksheet D: Bonding Introduction 1. What type of atoms combine to form a covalent bond? 2. What type of atoms combine to form a ionic bond? 3. What type of atoms combine to form a metallic bond? 4. Give two examples of a covalent compounds? 5. Give two examples of a ionic compounds? 6. Give two examples of a metallic compounds? 7. Describe how a covalent bond forms between two atoms. 8. How does a covalent bond differ from an ionic bond? 9. _________________is defined as the energy required to break the chemical bond between two atoms and separate them. 10. _________________is the tendency of an atom to attract bonding electrons to itself when it bonds with another atom. 11. _________________is the attraction between two atoms in which bonding electrons are shared _________________between two atoms 12. In general, if the difference in electronegativity between two atoms is zero the bond formed is _________________ 13. If the electronegativity difference between two atoms is between 0.5 and 2.1 the bond formed is _________________ - 18 - Name_________________ 14. If the electronegativity difference between two atoms is greater than 2.1, the bond is _________________ 15. In an ionic bond, the valence electrons are ___________. 16. In a metallic bond the valence electrons form a ______________________________ 17. Rank the bonds (ionic, covalent, metallic) in order from strongest to weakest. 18. Classify each of the following compounds as either: Ionic, Covalent, Metallic. a. b. c. d. e. f. g. h. i. j. k. l. m. n. o. p. q. r. s. H2O NaCl MgSO4 CsCl Fe Hg He Ca3(PO4)2 NH4Cl NH3 P2O5 Ag AgNO3 AgCl Titanium Barium Phosphate Sulfur Dioxide Bromine Tungsten V Bromide ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ ______________ - 19 - Name_________________ WS E: Lewis Structure Worksheet: (do on your own paper: this will take quite a bit of paper) Draw the Lewis Structures Determine the shape Determine the polarity of the molecule 1. HCl 2. Br2 3. SeBr2 4. CF4 5. PI3 6. O2 7. N2 8. H2 9. OI2 10. CS2 11. SiBr4 12. F2 13. HCN 14. NH4 + 15. NO2 – 16. SO3 17. SO4218. NO3- 19. 20. 21. 22. 23. 24. 25. 26. 27. 28. PO33CNCO2 CO I2 CO32SO2 OCNSCNO3 For the following structures: You do NOT have to determine the shapes 29. H3CCOOH 30.CH3CH2OH 31. H3COCH3 32. H3CCH3 33. H2CCH2 34. HCCH - 20 - Name_________________ WS F: Intermolecular Forces Substance #1 Predominant Intermolecular Force Substance #2 (a) HCl(g) I2 (b) CH3F CH3OH (c) H2O H2S (d) SiO2 SO2 (e) Fe Kr (f) CH3OH CuO (g) NH3 CH4 (h) HCl(g) NaCl (i) SiC Predominant Intermolecular Force Substance with Higher Boiling Point Cu 2. Rank the following substances in order from lowest to highest melting point. CO2, NaCl, Ag, H2O, He, HBr 3. Rank the following substances in order from lowest to highest freezing point. H2O, Ca3(PO4)2, Cr, C2H6, OF2 4. Rank the following substances in order from highest to lowest boiling point. Cl2, Ne, Ca, Cr(OH)3, CH3CH2OH, Diamond - 21 - Name_________________ WS A: History of the atom and Electron Configurations 1. Identify the two particles found in the nucleus of an atom. Proton--Neutron 2. What is an electron? Negatively Charged Particle in the Nucleus 3. Identify the scientists (Thompson, Bohr, Rutherford, or Newton) who proposed each of the models illustrated below: a. b. c. d. Bohr Dalton Rutherford Thompson 5. What specific evidence (from the gold foil experiment) led Rutherford to come to the each of the following conclusions? a. The nucleus occupies very little space in the atom. Only a few of the alpha particles hit the nucleus b. An atom is made of mostly empty space. Only a few of the alpha particles hit the nucleus c. The nucleus is positively charged. Alpha Particles are positively charged so they deflected. - 22 - Name_________________ 5. For each of the elements listed below, complete the following: d. long hand electron configuration e. orbital diagram (boxes with arrows) f. short hand electron configuration (begins with a noble gas) 2 2 6 1s 2s 2p 3s2 3p6 4s1 1. Li 2 1s 2s1 [He] 2s1 1s 2s 2. Na 1s2 2s2 2p6 3s2 3p1 1s 2s [Ne] 3s1 2p 3. K 1s2 2s2 2p6 3s2 3p64s1 1s 2s 3s [Ar] 4s1 2p 3s 4s 4. B 1s2 2s2 2p1 1s [He] 2s2 2p1 2s 2p - 23 - 3p Name_________________ 5. Al 1s2 2s2 2p6 3s2 3p1 1s [Ne] 3s2 3p1 2a p 2s 3s 3p 6. Ne 1s2 2s2 2p6 1s [He] 2s2 2p6 2s 7. Ar 1s2 2s2 2p6 3s2 3p6 1s 2p [Ne] 3s2 3p6 2s 2p 3s 2p 3s 3p 8. Mg 1s2 2s2 2p6 3s2 1s [Ne] 3s2 2s 9. P 1s2 2s2 2p6 3s2 3p3 1s 2s [Ne] 3s2 3p3 2p 3s - 24 - 3p Name_________________ 10. Ni 1s2 2s2 2p6 3s2 3p64s13d8 1s [Ar] 4s13d8 2s 4s 2p 3s 3p 3s 3p 3s 3p 3d 11. Zn 1s2 2s2 2p6 3s2 3p64s13d10 1s [Ar] 4s13d10 2s 4s 2p 3d 12. Br 1s2 2s2 2p6 3s2 3p64s13d10 4p5 1s 2s 4s [Ar] 4s13d10 4p5 2p 3d 4p 13. H 1s1 - 25 - Name_________________ 1s 14. He 1s2 1s 15. Ca2+ 1s2 2s2 2p6 3s2 3p6 1s 16. N31s2 2s2 2p6 1s Na1+ 1s2 2s2 2p6 [Ne] 3s2 3p6 2s 2p 3s [He] 2s2 2p6 2s 2p 17. 1s [He] 2s2 2p6 2s 2p - 26 - 3p Name_________________ WS B: Light and Light Equations Name ____________________ 1. If an electron goes from level 4 to level 2 what happens? Be specific. 2. Fill in the following table Violet Blue Green Yel Orange Energy (Joules) Wavelength-λ (meters) Frequency –ν (s-1) 6.3 x 10-19 J 8.28x10-19 J 6.62x10-34 J 1.5 x 10-14 J 1.99 x 10-26 J 1.48 x 10-20 J 3.78 x 10-19 J 3.15x10-7 m 2.4 x 10-7 m 3.00x106 m 1.32x10-11 m 10 1.36x10-5 m 525 nm 9.5 x 1014 s-1 1.2 x 1015 s-1 100 s-1 2.3 x 1019 s-1 3.0 x 107 s-1 2.2 x 1013 s-1 5.7 x 1014 s-1 - 27 - Red Color of Light/type of electromagnetic radiation UV UV Long Radio X-Ray Radio IR Green Name_________________ The diagram above represents the spectra of three different elements. Explain the following: d. Why are they different Each atom has different orbital levels. They each have the same orbitals (1s, 2s, 2p, etc). But each has a different value for energy. This then translates into different energy levels. The lines are made when electrons “fall” from a higher level to a lower level. They are different because the “height” of the levels is different in each atom e. Why are they not a continuous series of colors (ROYGBIV)? They are not continuous because the electrons can only have certain allowable energy levels. The electrons are said to be quantized. f. How are these used in the field of Astronomy? In astronomy these are used to identify the elements in the stars. - 28 - Name_________________ Part C: Periodicity Name ____________________ 1. List the following atoms in order of increasing electronegativity: a. Cr, Ni, Kr, Ga, K K < Cr < Ni < Ga < Kr b. P, As, F, Hg, Fr Fr < Hg < As < P < F 2. List the following atoms in order of increasing atomic radius: c. Cr, Ni, Kr, Ga, K Kr < Ga < Ni < Cr < K d. P, As, F, Hg, Fr F < P < As < Hg < Fr 3. List the following atoms in order of increasing ionization energy: e. Cr, Ni, Kr, Ga, K K < Cr < Ni < Ga < Kr f. P, As, F, Hg, Fr Fr < Hg < As < P < F 4. Why are alkali metals stored in kerosene or mineral oil? Why are they not allowed to sit out in the air? When they are exposed to air they lose their one valence electron and react. 5. The Mg+2, and the Na+1 ions each have ten electrons surrounding the nucleus. Which ion would you expect to have the smaller radius? The Mg+2 ion is smaller because it has one more proton which causes the electron cloud to be held more tightly, thus making it smaller. - 29 - Name_________________ Worksheet D: Bonding Introduction Name ____________ 1. What type of atoms combine to form a covalent bond? a. Non-Metal to Non-Metal 2. What type of atoms combine to form a ionic bond? Metal to Nonmetal 3. What type of atoms combine to form a metallic bond? Metal-Metal 4. Give two examples of a covalent compounds? CO, H2O, C6H12O6, etc 5. Give two examples of a ionic compounds? NaCl, Ca3(PO4)2, NH4Cl 6. Give two examples of a metallic compounds? Iron, Copper, Zinc, Brass 7. Describe how a covalent bond forms between two atoms. Valence Electrons Share 8. How does a covalent bond differ from an ionic bond? Ionic Bonds: valence electrons are transfered 9. Bond Energyis defined as the energy required to break the chemical bond between two atoms and separate them. 10. electronegativity is the tendency of an atom to attract bonding electrons to itself when it bonds with another atom. 11. Dipole Forcesis the attraction between two atoms in which bonding electrons are shared unevenly between two atoms 12. In general, if the difference in electronegativity between two atoms is zero the bond formed is Non-Polar - 30 - Name_________________ 13. If the electronegativity difference between two atoms is between 0.5 and 2.1 the bond formed is Polar 14. If the electronegativity difference between two atoms is greater than 2.1, the bond is Ionic 15. In an ionic bond, the valence electrons are Transferred 16. In a metallic bond the valence electrons form a Sea of valence electrons 17. Rank the bonds (ionic, covalent, metallic) in order from strongest to weakest. Covalent > Ionic > Metallic 18. Classify each of the following compounds as either: Ionic, Covalent, Metallic. a. b. c. d. e. f. g. h. i. j. k. l. m. n. o. p. q. r. s. H2O NaCl MgSO4 CsCl Fe Hg He Ca3(PO4)2 NH4Cl NH3 P2O5 Ag AgNO3 AgCl Titanium Barium Phosphate Sulfur Dioxide Bromine Tungsten V Bromide Covalent Ionic Ionic Ionic Metallic Metallic None Ionic Ionic Covalent Covalent Metallic Ionic Ionic Metallic Ionic Covalent Covalent Ionic - 31 - Name_________________ WS E: Lewis Structure Worksheet: Draw the Lewis Structures Determine the shape Determine the polarity of the molecule Name _________ 1.HCl Linear Diatomic Polar H Cl 1. 2.Br2 Br Br 2. Linear Diatomic Non Polar 3.SeBr2 Bent 104.5 Polar Se 3. Br Br 4.CF4 - 32 - Name_________________ F 4. Tetrahedral Non Polar C F F F 5.PI3 5. P I I I Pyrimidal Polar 6.O2 6. O O Linear Diatomic Non Polar 7.N2 - 33 - Name_________________ 7. N N Linear Diatomic Non Polar H Linear Diatomic Non Polar 8.H2 8. H 9.OI2 O 9. I I 10. CS2 10. S Bent 104 Polar C S Linear Triatomic Non Polar - 34 - Name_________________ 11. SiBr4 Br Si 11. Br 12. 12. 14. Br F2 F 13. 13. Br Tetrahedral Non Polar F Linear Diatomic Non Polar HCN H C Linear Triatomic Polar N NH4 + - 35 - Name_________________ H N 14. H H H Tetrahedral Non Polar 15. NO2 – - 36 - Name_________________ 15. O N O Bent 120 Polar 16. SO3 - 37 - Name_________________ O 16. O S O Trigonal Planar Nonpolar 17. SO42- - 38 - Name_________________ 2- O 17. O S O O Tetrahedral Nonpolar 18. NO3- - 39 - Name_________________ - O 18. O N O Trigonal Planar Nonpolar 19. PO33- - 40 - Name_________________ 3P O O Pyrimidal Polar 20. CN- C N Linear Diatomic Polar 21. CO2 - 41 - O Name_________________ 21. O C O Linear Triatomic NonPolar 22. CO C O Linear Diatomic Polar 23. I I2 I Linear Diatomic Non Polar - 42 - Name_________________ 24. CO32- O 24. O C O Trigonal Planar Nonpolar 25. SO2 Bent 120 Polar - 43 - Name_________________ 26. 26. OCN- O C N 1- Linear Triatomic Polar 27. 27. SCN- S C N 1- Linear Triatomic Polar 28. 28. O3 O O O - 44 - Bent 120 Nonpolar Name_________________ For the following structures: You do NOT have to determine the shapes 29. H3CCOOH H O H C C O H H 30. CH3CH2OH 31. H3COCH3 - 45 - Name_________________ H H H C O C H H H 32. 33. H3CCH3 H2CCH2 - 46 - Name_________________ 34. HCCH - 47 - Name_________________ WS F: Intermolecular Forces Substance #1 Name _______________ Predominant Intermolecular Force Substance #2 (a) HCl(g) Dipole I2 (b) CH3F Dipole CH3OH (c) H2O H-bonding (d) SiO2 Predominant Intermolecular Force Substance with Higher Boiling Point LDF HCl H-Bond CH3OH H2S Dipole H2 O Covalent Network SO2 Dipole SiO2 (e) Fe Metallic Kr LDF Fe (f) CH3OH H-Bond CuO Ionic CuO (g) NH3 H-Bond CH4 LDF NH3 (h) HCl(g) Dipole NaCl Ionic NaCl (i) SiC Covalent Network Metallic SiC Cu 2. Rank the following substances in order from lowest to highest melting point. CO2, NaCl, Ag, H2O, He, HBr He < HBr < H2O < Ag < NaCl 3. Rank the following substances in order from lowest to highest freezing point. H2O, Ca3(PO4)2, Cr, C2H6, OF2 C2H6 < OF2 < H2O < Cr < Ca3(PO4)2 4. Rank the following substances in order from highest to lowest boiling point. Cl2, Ne, Ca, Cr(OH)3, CH3CH2OH, Diamond Diamond > Cr(OH)3 > Ca > CH3CH2OH > Cl2 > Ca - 48 -