Matter Learning Targets Name:__________________________ Each of the following “Learning Targets” below are ideas or skills you need to know or do to be able to pass the unit. Circle either “Yes,” “Need practice,” or “No” for each learning target. If you didn’t circle “Yes”, look over the “In-Class Resources” and the “Additional Resources” for additional help. YES = I understand or can do it Circle One ↓ Yes Need practice No Yes Need practice No Yes Need practice No Yes Need practice Need Practice = I kind of get it Learning Targets I can ….. In-Class Resources 1. Describe the relative charges, masses, and locations of the protons, neutrons, and electrons in an atom of an element. 2. Explain the arrangement of the elements on the Periodic Table, including the relationships among elements in a given column or row. 3. Explain that isotopes of an element have different numbers of neutrons and that some are unstable and emit particles and/or radiation. 4. Describe the role of valence electrons in the formation of chemical bonds. No = I have no clue what I’m doing Additional Resources https://chemistry.osu.edu/~woodward/ch121/ch2_atoms.htm http://www.chem4kids.com/files/elem_pertable.html http://www.colorado.edu/physics/2000/isotopes/index.html http://wiki.answers.com/Q/What_role_do_valence_electrons_play_in_bonding No Yes Need practice 5. Draw Bohr models for the neutral atoms of elements 1-20. http://www.pcs.k12.va.us/tms/periodictable/index.htm http://www.slideshare.net/Rachzyla/bohr-model-how-to 6. Draw the Lewis-dot structures (electron dot diagrams) for elements 1-20. http://www.youtube.com/watch?v=ulyopnxjAZ8&safe=active http://www.roymech.co.uk/Related/Chemistry/Lewis_dot_structure.html No Yes Need practice No YES = I understand or can do it Need Practice = I kind of get it No = I have no clue what I’m doing YES = I understand or can do it Circle One ↓ Yes Need practice No Yes Need practice No Yes Need practice No Need Practice = I kind of get it Learning Targets In-Class Resources 7. Use the Periodic Table to determine the number of protons, electrons and neutrons in an atom of a given element. 8. Use the Periodic Table to determine the number of energy levels and valence electrons in an atom of a given element. 9. Describe trends across rows and down columns in the Periodic Table YES = I understand or can do it Need Practice = I kind of get it No = I have no clue what I’m doing Additional Resources http://www.college-cram.com/study/chemistry/atoms-and-molecules/using-theperiodic-table/ http://www.youtube.com/watch?v=wGz7uqMxddQ&safe=active http://www.college-cram.com/study/chemistry/atoms-and-molecules/using-theperiodic-table/ http://www.youtube.com/watch?v=wGz7uqMxddQ&safe=active http://chemistry.about.com/od/periodictableelements/a/periodictrends.htm http://www.chem.tamu.edu/class/majors/tutorialnotefiles/trends.htm No = I have no clue what I’m doing o l' \ ~COIVMI')S The Periodic Table of the Elements \ ~4--3 -;) +) \ ~ 3 Lithium Beryllium 6.941 9.012182 11 Na 12 Mg Sodium Magnesium 22.989770 20 Ca 5 W 21 Sc 31 Ga 26 Fe 32 Ge Calcium Zinc Gallium 65.39 69.723 72.61 48 49 In 50 Sn Rb Strontium Cd Molybdenum 85.4678 95.94 102.90550 55 Cs 74 W 77 78 Ir Pt . 132.90545 59 Pr -teN \0 ids 81 TI 82 Pb 83 Bi lllallillIn Lead 207.2 108 Hs 112 113 114 65 Tb 66 Dy 67 Ho Terbium Dysprosium 61 Iridium Pm 62 Sm Promelhill111 Samarium 144.24 (145) 150.36 92 93 Np 94 63 ..•. Yb 71 Lu Ytterbium Lutetium 68 Er Tm El'bium Thulium 164.93032 167.26 173.04 8 99 100 Pu Cf Es Fm 102 No 244) 251) (252 Liquid S ~f .••.. 1 Holmium Eu 16250 Uranium 231.03588 1995 IUPAC masses and Approved Names from htlp:l/ww'\\'.chclll gmw,ac.ukiillpilc/AtWt! masses for 107-111 from C&EN. March) 3, 1995. p. 35 112 from hllQ:i!ww\-v.<'si.dehI12c.hul1l 121.760 204.3833 U Protactinium Antimony Mercury 60 Nd NeodYlllill1n Tin 118.710 200.59 1 0:: me.+o.. \ S : nOn- me.to..ls Indium 114.818 190..23 Osmium Cesium ~ N\ e 5 26.981538 23 V 40.078 Rubidium R o Potassiurrt 38 Sr ~ W(iaht:- . 39.0983 37 5 A~mit. ~Mbo\ Atomi C.rtlA$s / 24.3050 19 K 4 4 AtOMi(. ~ 4 Be ~, ~ rOOM mOSt: r e ~ <...1 i\J -e.. pe.rQ.. tvv' e e le.rne.)'\ \-$ t-e.rY' Atomic # Element Column/Group/Family Radius Name Names A\ ~~\\ne Me:\-cd$ 5. Nd-ro~~ni;..m,I"12: Mko.\ir\t Eo.f"'f-h M~to-ls 6.~~e.n ~o.rnil~ 3: Boron Fc,..mi l~__ 7. "Q..\Q%o..=O\S~ _ 4: Co.rb"n ~OlY\i I~ 8. Noble 1iCl.S es 3 Lithium 152 4 Beryllium 111 5 Boron 86 6 Carbon 77 7 Nitrogen 70 8 Oxygen 73 9 Fluorine 72 Particle Charge Mass Location 10 Neon 71 Proton -+-\ Nvc...\ e.uS 11 Sodium 186 Neutron I ~t"\U \ Pt.MV 12 Magnesium 160 13 Aluminum 143 14 Silicon 118 15 Phosphorus 108 16 Sulfur 106 17 Chlorine 99 18 Argon 97 19 Potassium 232 20 Calcium 197 1: 0 ... \ Electron '4'00 AH\j of O~ v An ion is a Lt\le\~ v = the o.tomlC nvrnber The number of electrons = t be 0..-\-omi c.. Y\ v mbet"' The number of neutrons = RO\Jnc.\e& o..t()mit mCLSS - o.:h;>mi<.. rwmber The atomic number, or the number of are elements that have the same number of ~y-()n tf\er~1.( The number of protons tells you the identity Isotopes euS \,1\.><" \ ~r()\-ohS of an atom. VV'" C) fO\,\$ ,but different numbers S. cho.r~eO atom. Ions become charged by gaining or losing e\e,c...-n-O't\S Columns Columns go ~p c..nQ Qc:>wn on the Periodic Table. and ~m\ Columns are also called ~ \\t..S. The column number tells you the number of \/<:A \ Valence electrons are the electrons in the en<.e. O\ltS \ d.~ electrons. energy level. Rows Rows go hOY"\"2.onto..\l\.j- on the Periodic Table. Rows are also called ¥e.~\ods Rows tell you the number of t,Y\trC!l,C . le:.\lt-ls Alpha Decay: _ Beta Decay: _ Gamma Decay: _ Alpha Decay Example: _ Beta Decay Example: _ Science Spectrum Answer Key continued 6. In both cases, the variables are directly 7. 8. 9. 10. 11. 7. Charged particles move in response to a related. As one changes, the other changes in the same direction. pressure and amount of gas Direct; as one variable increases, the other variable increases. Yes; a straight-line graph shows a proportional relationship. Boyle’s law Inverse; as one variable increases, the other decreases. 8. 9. 10. 11. Review 1. Rutherford’s experiment showed that the Review 1. The particles in a gas bump each other 2. 3. 4. 5. and the walls of the container, producing pressure. Gay-Lussac’s Law; as temperature increases, pressure increases. In summer, the temperature of the air inside the tires would be higher than in the winter and pressure would increase. The temperature of the particles in the balloon would increase. When temperature increases, the volume of the gas will increase and the balloon will increase in volume and may break. Charles’s law predicts this result. Temperature and pressure are inversely related. As one variable increases, the other decreases. Students should draw a graph with temperature on the x-axis and pressure on the y-axis. They should draw a straight line from the origin to the top right corner. Possible title: “Pressure Versus Temperature for a Gas at a Constant Volume” 2. 3. 4. 5. 6. 7. 1. protons and neutrons 2. The mass of an electron is much smaller than the mass of a proton. 3. two 4. They have the same number of protons as SECTION 1 THE DEVELOPMENT OF ATOMIC THEORY 1. the Greek word atomos OR a Greek word 4. 5. 6. positive charge in an atom is concentrated in a nucleus at its center. Possible answer: The law of definite proportions states that the relative masses of elements in a compound are always the same. Both Dalton and Democritus thought that an atom was a tiny, indivisible particle. In Thomson’s atomic theory, electrons were embedded in a mass of positive charge. In Rutherford’s atomic theory, electrons orbited a dense, positively charged nucleus. He concluded that the particles came from atoms in the cathode and that the particles were the same in atoms of different elements. There are 164 g of nitrogen in 200 g of ammonia. There are 27 g of hydrogen in 150 g of ammonia. SECTION 2 THE STRUCTURE OF ATOMS Chapter 4 Atoms 2. 3. magnet, but light rays do not. In Thomson’s model, the atom contains smaller particles. In Dalton’s model, the atom was indivisible. They would either pass straight through or be deflected slightly. He repeated the experiment. Student should label the nucleus “positive” and the electrons “negative.” 5. 6. 7. 8. 9. 10. 11. 12. 13. meaning “unable to be cut or divided” There was no evidence to support it. Dalton had scientific evidence to support his theory. 24 g New observations did not support Dalton’s theory. the anode electrons. the electric force It has 13 protons and 13 electrons. They can have different numbers of neutrons. one atomic number8; mass number 16 17 18 the unified atomic mass unit 35.453 u Copyright © by Holt, Rinehart and Winston. All rights reserved. Interactive Reader 5 Answer Key Science Spectrum Answer Key continued 14. the basic unit used to measure the amount 15. 16. 17. 18. 13. Student should label the image with both of a substance 29 g 24.3 g/mol molar mass of Cu63.55 g/mol; (3.20 mol Cu) × (63.55 g Cu/mol Cu) 203 g Cu molar mass of C12.01 g/mol; molar mass of H 1.01 g/mol; molar mass of CH4 (12.01 g/mol) + (4) × (1.01 g/mol) 16.05 g/mol electrons in one energy level “ground state” and should label the other image “excited state” Review 1. s or p 2. Energy levels contain orbitals. 3. The first energy level contains two 4. Review 1. Mass number is the number of protons and 2. 3. 4. 5. neutrons in the nucleus of an atom. Atomic mass is the mass of a single atom in grams or in unified atomic mass units. top row: 7 second row: 7 third row: 27 fourth row: 37 bottom row: 87 Atoms A and B have the same atomic number but different mass numbers, so they are isotopes. Atom D contains 37 protons. Since atoms are neutral, it must also contain 37 electrons. molar mass of glucose 180.2 g/mol; (300 g glucose)(180.2 g/mol) 1.66 mol 5. 6. 7. Chapter 5 The Periodic Table SECTION 1 ORGANIZING THE ELEMENTS 1. atomic mass 2. Scientists had not yet discovered elements SECTION 3 MODERN ATOMIC THEORY 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. electrons. The second energy level contains the other five electrons. An atom of nitrogen has two electrons in the first energy level and five in the second. The second energy level is the outermost energy level, so nitrogen has five valence electrons. We can’t know an electron’s exact location, speed, or direction in an atom. The electrons in an aluminum atom are located in the first, second, and third energy levels. It has two electrons in the first energy level, eight in the second energy level, and three in the third energy level. The third energy level is the outermost energy level, so aluminum has three valence electrons. with the properties that fit the pattern. Mendeleev predicted that scientists would find those elements. 3. Te and I did not fit the pattern of chemical properties unless they were put in the wrong order of atomic mass. 4. atomic number 5. The group it is in; elements in a group have similar chemical properties. Properties of elements change across a period. It must gain energy. lost Bohr’s model worked only for hydrogen. a region in an atom in which an electron is most likely to be Student should label the large shaded region around the nucleus “orbital.” In both models, electrons can be located only in certain energy levels. the first and second electrons in the outer energy level of an atom two They lie along different directions in space. 10 the lowest state of energy of the electron Review 1. The chemical properties of oxygen are more similar to those of sulfur because they are members of the same group. Elements in the same group share similar properties. Copyright © by Holt, Rinehart and Winston. All rights reserved. Interactive Reader 6 Answer Key The Periodic Table Journey Today you are going to go on a journey of discovery about the periodic table. To make it even more realistic, you are actually going to travel on a journey. The information that you need is placed around the school and you will travel to find it. To make this work we have to have some ground rules, so here goes: 1. You must stay with your group. 2. Go in order – the locations are listed for each section, when you finish one go to the next one down the list. 3. Only one group at a spot at a time. 4. You may not bother any other classes. 5. You may not be loud in the hallways. Please write all of your answers in this packet and then place this in your 3-ring binder. Have a pleasant journey and don’t forget to write! Transition Metals (Door W1) 1. Where do you find the transition metals on the Periodic Table? (If you haven’t been to the “The Periodic Table” spot or through the “Label Loop”, you won’t be able to answer this question yet.) They are found in the middle of the Periodic Table (the shorter columns). 2. List 5 properties that transition metals have. A. B. C. D. E. 3. What are the only magnetic transition metals? 4. List some special properties of the following transition metals: Platinum: Nickel: Silver: Iron: Nonmetals (Door W2) 1. Where do you find the nonmetals on the Periodic Table? (If you haven’t been to the “The Periodic Table” spot or through the “Label Loop”, you won’t be able to answer this question yet.) On the right side of the Periodic Table 2. What nonmetals are solids at room temperature? 3. What nonmetal is a liquid at room temperature? Bromine 4. List some special properties of the following nonmetals: Hydrogen: Helium: Carbon: 5. What nonmetals are present in the air that you breathe? Isotopes (Door W3) 1. What is the definition of an isotope? Isotopes are atoms with the same number of protons and different numbers of neutrons. 2. What is the “Nucleon Number”? The nucleon number is the sum of the protons and the neutrons. 3. What is the name that we have been using for the nucleon number? Atomic Mass 4. What two isotopes are listed on the poster? Carbon – 12 and Carbon - 14 5. What is the difference between the two isotopes from the question #4? Carbon – 14 has two more neutrons than Carbon – 12. 6. What is the same for the two isotopes from question #4? Both isotopes have the same number of protons. What is an Element? (Door E4) 1. What is the definition of an element? 2. How many of the known elements are naturally occurring? 3. What are allotropes? Give an example. Allotropes are different forms of the same element. Coal, graphite and diamond are all allotropes of carbon. 4. What are the two most abundant elements in the Universe? Hydrogen and Helium 5. What are the five most abundant elements in your body? What percent of your body do they make up? 6. What are the two rarest elements on earth? How to Read the Periodic Table (Door E3) 1. What does the atomic number tell us about an element? The atomic number tells you the number of protons and electrons in an atom. 2. What does the atomic weight (mass) tell us about an element? The atomic weight (mass) is the sum of the protons and neutrons in an atom. 3. What do the rows on the Periodic Table tell us? The row number tells you the number of energy levels (rings of electrons) that an atom has. 4. What do the columns on the Periodic Table tell us? The columns tell you the number of valence electrons an atom has. 5. How do you find the number of neutrons that an atom of an element has? # of neutrons = atomic mass – atomic number Metals (Main Office Door) 1. Where do you find the metals on the Periodic Table? (If you haven’t been to the “The Periodic Table” spot or through the “Label Loop”, you won’t be able to answer this question yet.) You find the metals on the left side of the Periodic Table. 2. List six common properties of metals: A. B. C. D. E. F. 3. What are alloys and why are they so useful? 4. What are ores? 5. Why are metalloids? Metalloids are elements that have properties of both metals and non-metals. The Periodic Table (Door E2) 1. Who drew up the first periodic table? When did he do this? Dmitri Mendeleev 2. What are the columns called? Groups or Families 3. What are the rows called? Periods 4. What happens to the size of the atoms as you go across a row (period)? 5. What happens to the size of the atoms as you go down a column (group)? 6. How can we use the Periodic Table to make predictions about elements and compounds? Active Metals (By Our Fire Exit Door) 1. Where do you find the active metals on the Periodic Table? 2. Why do we call them active metals? We call them active metals because they are very reactive. 3. What do all of the Alkali Metals have in common? 4. What do all of the Alkali-Earth Metals have in common? 5. Which two active metals are radioactive? 6. What is one of the earth’s most abundant metals? Where do you find it in you? Calcium is one of the most abundant metals on Earth. You have calcium in your bones. 7. What active metals do our bodies need small amounts of? Sodium and Potassium The Label Loop Starting at A207 (that room sounds familiar) go around the loop and label the things on your Periodic Table. You will need an assortment of colored pencils for your group (eight should do it). When you get back to A207, you are done with this station. Protons, Neutrons, and Electrons Practice Worksheet Element Name Atomic symbol Atomic Mass (rounded) Atomic number Protons Neutrons Electrons Valence Electrons Boron B 11 5 5 6 5 3 Metal, Metalloid or Non metal Metalloid Sodium Na 24 11 11 13 11 1 Metal Gallium Ga 68 31 31 37 31 3 Metal Yttrium Y 89 39 39 50 39 3 Metal Copper Cu 64 29 29 35 29 1 Metal Technetium Tc 98 43 43 55 43 7 Metal Lead Pb 207 82 82 125 82 6 Metal Ytterbium Yb 173 70 70 103 70 2 Metal Actinium Ac 227 89 89 138 89 5 Metal Molybdenum Mo 96 42 42 54 42 6 Metal Thallium Tl 204 81 81 123 81 5 Metal Fermium Fm 257 100 100 157 100 8 Metal Nobelium No 259 102 102 157 102 2 Metal Hydrogen H 1 1 1 0 1 1 Non-metal Carbon C 12 6 6 6 6 4 Non-metal Nitrogen N 14 7 7 7 7 6 Non-metal Barium Ba 137 56 56 81 56 4 Metal Helium He 4 2 2 2 2 2 Non-metal Calcium Ca 40 20 20 20 20 2 Metal Silicon Si 28 14 14 14 14 4 Metalloid Argon Ar 40 18 18 22 18 8 Non-metal Magnesium Mg 25 12 12 13 12 2 Metal Seaborgium Sg 265 106 106 159 106 6 Metal Periodic Table Puzzle - Answer Key Down: 1. IRON - I have 26 protons. 3. HYDROGEN - I am not really an alkali metal, but since I have only 1 electron I behave like them. 4. NICKEL - I am a metal with 28 electrons. 7. ALUMINUM - I am a member of the boron family and am the most abundant metal in the Earth’s crust. 8. OXYGEN - I am a gas with 8 protons and 8 neutrons. 10. LEAD - I am a member of the carbon family often mistaken for the end of your pencil. 12. MERCURY - I am a metal that is liquid at room temperature. 14. SILVER - My atomic number is 47 and I am used to make photographic film. 15. CALCIUM - I have 20 neutrons and am found in your teeth and bones. 16. PHOSPHORUS - I am a member of the nitrogen family with 16 neutrons. 18. FLUORINE - I am a gas with a mass number of 19. 19. POTASSIUM - I am the first element in the fourth period used in making fertilizer. 22. TIN - You can find me in the carbon family in the fifth period. Across: 2. CHLORINE - My atomic mass is 35.453. 5. SULFUR - I have 2 electrons in the first shell, 8 in the second shell, and 6 in the third shell. 6. CARBON - I am the head of the carbon family known as the “basis of life”. 9. GOLD - My atomic number is 79. 11. MANGANESE - I am a transition metal with 25 electrons. 13. NITROGEN - I make up 78% of the air and am found in the 15th group. 14. SODIUM - I am a silvery white metal used to make salt. 17. MAGNESIUM - I am a member of the alkaline earth metals used to make fireworks and medicines. 20. HELIUM - I am a noble gas with 2 electrons. 21. SILICON - I am the 2nd most abundant element in the Earth’s crust and have 14 neutrons. 23. IODINE - I am a member of the halide family with an atomic number of 53. 24. ZINC - I am a transition metal with 30 electrons useful in making paint. 25. BROMINE - I am the only element in the halide family that is a liquid. History of the Atom Notes Fill in the following table: Who and When What Democritus 400 BC Said that all matter was made out of atoms. He didn’t have any evidence to back up his model. Aristotle 350 BC Said that all matter was a combination of the Four Essential Elements: Air, Fire, Water and Earth. He didn’t have any evidence to back up his model, but his idea was accepted as truth for 2,000 years. Said that all matter was composed of atoms. AN atom was a solid, positively charged particle (like a jaw breaker or a marble). Dalton is credited with discovering the proton. Dalton had evidence to back up his model. Using cathode rays, he discovered the electron - a negatively –charged particle in the atom. Thomson’s model of the atom was of a chocolate chip cookie. The cookie part was the positively charged stuff from Dalton’s Model and the chocolate chips were the electrons embedded in the cookie. Performed the famous “Gold Foil Experiment”. He discovered the nucleus. Rutherford’s model of the atom was of a nucleus (where the protons were located) in the center with electrons orbiting around it. Discovered the neutron. The neutrons were determined to be in the nucleus of the atom. John Dalton J.J. Thomson Ernest Rutherford Chadwick Niels Bohr Developed the Bohr Model of the Atom where you had a nucleus with protons and neutrons and the electrons orbiting around it in specific orbitals. Electrons couldn’t be just anywhere. Werner Heisenberg Their discoveries lead to the modern “Electron and Erwin Schrödinger Cloud Model of the Atom”. In this model the electrons are everywhere, but the most likely place to find them is in Bohr’s orbitals. Name: Hour: Date: Chemistry: Atomic Number and Mass Number Complete the following chart and answer the questions below. Number of Protons Atomic Number Element Name b r; 8 ff 8 fb I { 0 1 G 6 hydrogen Grbot., hydrogen ( nitrogen ( '1 ( { "'rclh:>~~ U rq t\ ,'t.d",., ~0 cesium ~ !~ L.\""- 11 tungsten 13 ~1V\.,'ho &V'~.'4 """"' silver 3 2 '7 14 2 146 d-3R' S'~ 82 ( :Sf) LJ 12 J.3 9~ L('J 47 b I 108 'It{ SS- '1t.{ 110 toL( .ss- 45 80 24 ~r 52 (,3 63 89 152 L(') l1"J bO 107 0(, 76 CJ"S "","1'tA"-. 14 1 ex V( c..kto~'~~ 12 0 I 92 ~; lvev- Mass Number b carbon O'A.,.. . . Numberof Neutrons ICfo 114 How are the atomic number and the number of protons related to each other? Ato~~/c. 41 r =: -4 of- Al:> fot\.~ How do the number of protons, number of neutrons, and the mass number relate to each other? p rcf"ot'\.5 -+ p\eUft'"D1/\.5 =- f\-.Pcs s 'f:/ What is the one thmg that determines the identity of an.atom (that is, whether it is an oxygen atom or a carbon atom, etc.)? n<>- p.--"" 10",,- Atomic Theory and the Periodic Table L M F S o M6NO o L o B 7 H R... 0 H o 10 :r 12 11 EN6Reo)' r: 0 b L l--l T 0 s o 6 E tV .s T 0 (] oN . • ' The Great Periodic Table/Atomic M&M Treasure Huntl Today you are going on a treasure hunt. Your goal is to unlock the secrets of the Periodic Table! Each clue, each new discovery will unlock the Periodic Table's secrets and lead to more clues which will lead you to even deeper mysteries and even greater when I say that the Periodic Table is the single most important The Periodic Table is the ingredients understand understandings! scientific I am not kidding document ever made. list for the Universe - if you understand how it works, you the basis of EVERYTHING! Good luck and, as the great Sherlock Holmes would say, "The hunt is on!" Part One: The Plan The plan for you today is to build Bohr Models of atoms using your Periodic Table and M&Ms. Think of today as your chance to put everything take your understanding together that we have learned so far and to of the Periodic Table to new levels. Materials Each person will need to get 60 M&Ms for this lab (3 different colors, 20 of each color). Each person will need to put his or her M&Ms a double layer of paper towels. One large sheet of white paper per person (on the workbench in the lab area). Each person will need his/her Periodic Table. DO NOT EAT ANY M&Ms UNTIL YOUR ENTIRE GROUP IS DONE WITH THE LABII!! Part Two: The Set-Up 1. Get all of your materials. 2. Divide your M&Ms into three groups (based on color). Label one group protons, one group neutrons and the last grou'p electrons. 3. Draw three big concentric circles on your white sheet of paper. The smallest should be at least 4" across. These will represent the energy levels where the electrons go. Part Three: The Lab 1. You are going to fill out the information build the model first on the tables on the next 2 pages. You need to and then fill out the corresponding Hydrogen as an example for you. 2. While you are going through this activity, part of the table. I have done look for any connections between the element model and its' placement on the Periodic Table. 3. Use your Periodic Table as necessary. 4. Work with your partners. Don't get ahead of your lab group! NOTE: When your 9f.Q.MP has filled out the tables, cleared to eat your M&Msl you are Element Cl 7J c :E ~ 0 3 ~ ~ H Li Be B C N Bohr Model Drawing 1 1 1 2 lP~ On Atomic # Ie ~~~ I~ J 2 3 2 4p \ ~ S,., ) 2 2 " 6 F 7 2 Atomic Mass #of Neutrons # of Energy Levels # of Valence Electrons 1 1 1 1 0 1 1 3 3 3 7 4 2 1 4 4 4 9 5 2 2 5 5 5 11 6 2 3 6 6 6 12 6 2 4 7 7 7 14 7 2 5 8 8 8 16 8 2 6 9 9 9 19 10 2 7 10 10 10 20 10 2 8 ) '), t 5~)L 'I #of Electrons '\ r-,p ') 5 #of Protons ) J...~ 3e. b 4 t \ J ~p 2 b""l a Ne 0 ) ~ ~ / / "1f ) ') ~t., J..~ ~e J J qpJ 8 2 2 \ ;)<! (~) top' " :<t2. (o~ ) 1~ ) \ z~ / Build models of the elements below. Fill out the table as you go along. Work with your group - don't get ahead of your partners! Look for any patterns/similarities with an element and its' place on the Periodic Table. Element ]:J 0 ~~ c :E 3 =l:t: ~ Na Mg AI Si Bohr Model Drawing Up '\ 1 3 t~ Atomic # '\ ~Q.. #of Proton s #of Electrons Atomic Mass #of Neutrons # of Energy Levels # of Valence Electrons '\ (e.- II 11 11 23 12 3 1 12 12 12 24 12 3 2 13 13 13 27 14 3 3 t{f<- 14 14 14 28 14 3 4 5~ 15 15 15 31 16 3 5 16 16 16 32 16 3 6 17 17 17 35 18 3 7 18 18 40 22 3 8 ~ VI) ) ) l~p'1 "\ \ 2 3 fd '" ) )) l~p 3 3 , 3 , ~~ \ 1«., ~~ ,~ ~"') 4 1e ~C2. ~ r"p ~) )&- "\ J ('1Y1 P 5 3 5 6 3 CI 7 3 Ar 8 3 {Sf' {6Y1 \ \~ ~ ~~ )ft- (b? '\ (6 ') 2..e. ~e... ~ e.. h ) -) ) {~f (<l ') \ '\ ~ ;<e. ~ e 011:~ J / ) lif' '" \ \, ~~7 ~~. ~)~ 18 , Part Four: Searching For the Clues In this section, you are going to look for patterns/similarities/trends in the rows and the columns of the Periodic Table. Use your tables from above and your Periodic Table to answer the following questions. Look for clues in the numbers and in your drawings. Part 1: The Rows The two tables that you filled out are for the 2nd and 3rd rows of the Periodic Table. Look at each row carefully. 1. What thing(s) remain the same for each element in a given row? The number of energy levels remains the same for elements in the same row. 2. A trend or pattern the temperature is a regular, consistent change (i.e. as we go from winter to summer, trends upward). What trends or patterns do you see as you go from left to right across the 2nd row? (Find at least three.) The number of protons, electrons and valence electrons all increase by one as you go across the row. The atomic mass increases and the number of neutrons generally increases. 3. Do the trends and patterns that you discovered in question #2 hold true for the third row of the Periodic Table, too? Yes 4. Look over the rest of the Periodic Table. Do your trends/patterns hold true for all elements? Yes 5. Share your findings with the group next to you. Did they find the same clues? Write down any new clues that they found. 6. Show your findings to the teacher and get his initials here: _ Part 2: The Columns The two tables that you filled out represent columns 1-8 of the Periodic Table (only the first few elements of each column). 1. What thing(s) remain the same for each element in a given column? The all have the same number of valence electrons. 2. A trend or pattern the temperature is a regular, consistent change (i.e. as we go from winter to summer, trends upward). What trends or patterns do you see as you go down a column? (Find at least three.) The number of energy levels goes up by one as you go down a column. The number of protons, electrons and neutrons increases as you go down a column. 3. Do the trends and patterns that you discovered in question #2 hold true for all of the columns? Yes 4. Look over the rest of the Periodic Table. Do your trends/patterns hold true for all elements in each column? Yes 5. Share your findings with the group next to you. Did they find the same clues? Write down any new clues that they found. 6. Show your findings to the teacher and get his initials here: _ Part Five: Sharing Your Findings with the Class For this part, we are going to come up with a class list of the trends, similarities and patterns that we discovered on the Periodic Table. Write down the agreed upon items below: Row Clues: Column Clues: Part Six: Blazing a New Traill Trends, patterns and similarities are no good if you can't use them. You are going to take what you have learned and predict the properties of elements that haven't even been discovered yet! This is exactly what scientists do - they take what they know and use it to help them discover new things! In the table below, I want you to tell me about the as yet undiscovered elements from row 8 of the Periodic Table. To make things a little easier, we will only do the elements for columns 1 through 8 (the ones you numbered at the top of your Periodic table). <1 0 1:J 0 c :E ::s :t:t: 3 :t:t: 1 8 2 8 3 8 4 8 5 8 6 8 7 8 8 8 . Bohr Model Drawing (draw the rings, but only label the outside ring electron number) Atomic # '\ 119 ))1) 120 p 133 ))))) ~I)~ 133 13'fp jJ))) ~ ~~ 134 (3~p ))))))/ ~ 135 (~bF))))) ) ~~ 136 131t ))j)))) }- 137 (~rf I J))) )) ~e 138 , f1~p )))))) J~ ) f~Of ~I ~ #of Protons #of Electrons 119 119 120 120 133 133 134 134 135 135 136 136 137 137 138 138 Atomic Mass #of Neutrons - - - - - - - - - - - - - - - #of Energy Levels 8 8 8 8 8 8 8 8 #of Valence Electrons 1 2 3 4 5 6 7 8 Lewis - Dot Structures In chemistry, the valence electrons are the most important thing to keep track of for an atom. A Lewis-Dot structure is a way of showing just the valence electrons of an atom. • H oe He • 0 Li • No • K Things - • • Be • B• • • • Mg • AI • • Q., • C. • N. '» • • • Si • . p. • •• • -. : o. • : F. -. : S. •• • •• -. : CI•• •• ~- : Ne •· •• :Ar: •• ••• • Co to know for this unit's test: Knowthe history of the atom (who discovered what part) Knowthe three parts of the atom, their charges, masses and where you find them) Knowhow to draw Bohr Model Diagrams Knowhow to draw Lewis-Dot Structures Knowhow to read your Periodic Table (protons, neutrons, electrons, energy levels, valence electrons, trends in rows and columns) The Periodic Table of the Elements (with Ionization Energies) 1 18 Hydrogen Alkali metals Alkaline earth metals Transition metals Lanthanides Actinides Other metals Metalloids (semi-metal) Nonmetals Halogens Noble gases 1 H 1.01 1312 2 Lithium Beryllium 3 4 Li Be 6.94 9.01 520 Sodium 900 Element name Helium Mercury 2 Atomic # 80 He Hg Symbol First ionization energy (kJ/mol) 200.59 Avg. Mass 1007 13 14 15 16 17 Boron Carbon Nitrogen Oxygen Fluorine 2372 Neon 5 6 7 8 9 10 B C N O F Ne 10.81 12.01 14.01 16.00 19.00 20.18 801 Magnesium 4.00 Aluminum 1087 1402 1314 Silicon Phosphorus Sulfur 1681 Chlorine 2081 Argon 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 22.99 24.31 26.98 28.09 30.97 32.07 35.45 39.95 496 738 3 4 5 6 7 8 9 10 11 12 578 787 1012 1000 1251 1521 Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.61 74.92 78.96 79.90 83.80 419 Rubidium 590 633 Strontium Yttrium 659 Zirconium 651 Niobium 653 717 763 Molybdenum Technetium Ruthenium 760 Rhodium 737 Palladium 746 Silver 906 Cadmium 579 Indium 762 Tin 947 Antimony 941 1140 Tellurium Iodine Krypton 1351 Xenon 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.47 87.62 88.91 91.22 92.91 95.94 (98) 101.07 102.91 106.42 107.87 112.41 114.82 118.71 121.76 127.60 126.90 131.29 710 720 868 558 709 403 Caesium 550 Barium 55 56 Cs Ba 132.91 137.33 376 503 Francium Lutetium 57-70 * Radium 87 88 Fr Ra (223) (226) 380 600 ** 509 *lanthanides Tantalum 684 Tungsten 702 Rhenium Osmium Iridium 804 Platinum 731 Gold Mercury Thallium Lead 834 Bismuth 869 Polonium 1008 Astatine 1170 Radon 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 174.97 178.49 180.95 183.84 186.21 190.23 192.22 195.08 196.97 200.59 204.38 207.20 208.98 (209) (210) 524 659 770 760 840 880 870 890.1 1007 589 716 703 812 890 1037 Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununquadium Ununpentium Ununhexium Ununseptium Ununoctium Rutherfordium 761 Dubnium Seaborgium Bohrium Ununtrium (222) 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Uuq Uup Uuh Uus Uuo (262) (267) (268) (271) (272) (270) (276) (281) (285) (284) (289) (288) (293) (294?) (294) --- --- --- Ytterbium 470 580 --- --- --- --- --- (280) --- --- --- --- --- Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium 57 58 59 60 61 62 63 64 65 66 67 68 69 70 La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb 138.91 140.12 140.91 144.24 (145) 150.36 151.97 157.25 158.93 162.50 164.93 167.26 168.93 173.04 538 534 545 547 573 581 589 Actinium **actinides Hafnium 652 Lu Lawrencium 89-102 640 Thorium 527 533 Protactinium Uranium 540 Neptunium Plutonium Americium 593 Curium 566 Berkelium Californium Einsteinium Fermium 597 Mendelevium 603 Nobelium 89 90 91 92 93 94 95 96 97 98 99 100 101 102 Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No (227) 232.04 231.04 238.03 (237) (244) (243) (247) (247) (251) (252) (257) (258) (259) 499 587 568 598 605 585 578 581 601 608 609 627 635 642 --- The Periodic Table of the Elements (including Atomic Radius) 1 18 Hydrogen Alkali metals Alkaline earth metals Transition metals Lanthanides Actinides Other metals Metalloids (semi-metal) Nonmetals Halogens Noble gases 1 H 1.01 31 2 Lithium Beryllium 3 4 Li Be 6.94 9.01 128 96 Element name Helium Mercury 2 Atomic # 80 He Hg Symbol 200.59 Atomic radius (picometers) Avg. Mass 14 15 16 17 Boron Carbon Nitrogen Oxygen Fluorine 28 Neon 5 6 7 8 9 10 B C N O F Ne 10.81 132 4.00 13 12.01 84 14.01 76 16.00 71 19.00 66 20.18 57 58 Sodium Magnesium Aluminum Silicon Phosphorus Sulfur Chlorine 11 12 13 14 15 16 17 18 Na Mg Al Si P S Cl Ar 22.99 24.31 26.98 28.09 30.97 32.07 35.45 39.95 166 141 3 4 5 6 7 8 9 10 11 12 121 111 107 105 102 Argon 106 Potassium Calcium Scandium Titanium Vanadium Chromium Manganese Iron Cobalt Nickel Copper Zinc Gallium Germanium Arsenic Selenium Bromine 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 39.10 40.08 44.96 47.88 50.94 52.00 54.94 55.85 58.93 58.69 63.55 65.39 69.72 72.61 74.92 78.96 79.90 83.80 203 Rubidium 176 170 Strontium Yttrium 160 Zirconium 153 Niobium 139 139 132 Molybdenum Technetium Ruthenium 126 Rhodium 124 Palladium 132 Silver 122 Cadmium 122 Indium 120 Tin 119 Antimony 120 120 Tellurium Iodine Krypton 116 Xenon 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe 85.47 87.62 88.91 91.22 92.91 95.94 (98) 101.07 102.91 106.42 107.87 112.41 114.82 118.71 121.76 127.60 126.90 146 142 144 142 139 220 Cesium 195 Barium 55 56 Cs Ba 132.91 137.33 244 215 Francium Radium 87 88 Fr Ra (223) (226) 260 190 Lutetium 57-70 * ** Tungsten 147 Rhenium Osmium Iridium 139 Platinum 145 Gold Mercury Thallium Lead 139 Bismuth 138 Polonium 139 Astatine 131.29 140 Radon 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn 174.97 178.49 180.95 183.84 186.21 190.23 192.22 195.08 196.97 200.59 204.38 207.20 208.98 (209) (210) 187 175 162 151 144 141 136 136 132 145 146 148 140 150 150 Ununoctium 170 (222) Rutherfordium Dubnium Seaborgium Bohrium Hassium Meitnerium Darmstadtium Roentgenium Copernicium Ununtrium Ununquadium Ununpentium Ununhexium Ununseptium 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 Lr Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Uuq Uup Uuh Uus Uuo (271) (272) (270) (276) (281) (285) (284) (289) (288) (293) (294?) (294) --- --- --- Ytterbium (262) (267) --- (268) --- --- --- --- --- --- (280) --- --- --- --- --- Lanthanum Cerium Praseodymium Neodymium Promethium Samarium Europium Gadolinium Terbium Dysprosium Holmium Erbium Thulium 57 58 59 60 61 62 63 64 65 66 67 68 69 70 La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb 138.91 140.12 140.91 144.24 (145) 150.36 151.97 157.25 158.93 162.50 164.93 167.26 168.93 173.04 207 204 198 198 192 192 189 Actinium **actinides Tantalum 154 71 221 *lanthanides Hafnium 164 Lu Lawrencium 89-102 175 Thorium 203 201 Protactinium Uranium 199 Neptunium Plutonium Americium 196 Curium 194 Berkelium Californium Einsteinium Fermium 190 Mendelevium 187 Nobelium 89 90 91 92 93 94 95 96 97 98 99 100 101 102 Ac Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No (227) 232.04 231.04 238.03 (237) (244) (243) (247) (247) (252) (257) (258) 215 206 200 196 190 187 180 169 --- (251) --- --- --- --- (259) --- --- Name______________________ Graphing the Periodic Table Define the following: GROUPS: Groups are also called columns or families. PERIODS: Periods are also called rows. Background/Explanation: The atomic radius is the distance from the nucleus of an atom out to the furthest valence electron. The atomic radius tells you the size of an atom. The larger the radius, the larger the atom. Procedure: 1. Use the Periodic Table provided to graph the Atomic Radius vs. the Atomic Number for elements 3-20. 2. Use the Periodic Table provided to graph the Atomic Radius vs. the Atomic Number for Groups 1 and 2. Graph 1: Atomic Number Vs Atomic Radius for elements 3-20 Questions for Graph #1: 1. Within a period, as the atomic number increases, the radius of an atom __decreases___. 2. What causes your graph to “jump” from elements 10 to 11 and 18 to 19? (Hint: Look at your Periodic Table!) You are starting a new row on the Periodic Table. 3. What is periodic (look for repeating patterns) about your graph? At the beginning of a row, the atomic radius is the highest and it goes down as you go across the row. Graph #2: Atomic Number vs. Atomic Radius for Groups 1 & 2 Questions for Graph #2: 4. Within a group, as the atomic number increases, the atomic radius __increases_____. 5. Which generally has larger atoms Group 1 or Group 2? __Group 1____ 6. Where do you think Group 3 would belong on this graph? Draw a dashed line in this location. Group 3 would be a curve just like groups 1 & 2, except that it would be beneath them. Analysis Questions (questions for BOTH graphs): 7. Going down a group, what is the trend for atomic size? The atom radius increases. 8. Explain the trend form question #7. Give reasons for why it happens. Every time you go down one element in a column, you are adding another energy level to the atom. 9. Going across a period, what is the trend for atomic radius? When you go across a period the atomic radius decreases. 10. Explain the trend form question #9. Give reasons for why it happens. It doesn’t make sense that the atomic radius decreases as you go across a row, because at the same time you are adding more stuff (protons, neutrons and electrons) to each atom. You have to remember that the protons and electrons are oppositely charged and that means that they are attracted to each other. You also have to remember that atoms with full outside energy levels (or 8 electrons in the outside energy level are more stable than other atoms. A more stable atom means that the atom is in a lower energy state and that means that the electrons are actually closer to the nucleus (where the protons are located). A Bonus Trend: Look at the graph below and answer the questions that follow. Boiling & Melting Points of a Group 1. What happens to the boiling and melting points as you go down this column? As you go down the column, the boiling points and melting points increase. 2. Which elements are gases at room temperature? Fluorine and chlorine are gases at room temperature. 3. Which element would be a liquid at room temperature? Bromine is a liquid at room temperature. 4. Which element is a solid at room temperature? Iodine is a solid at room temperature. 5. On the planet Vulcan, room temperature is -20 °C. What state will bromine be in at that temperature? Bromine will be a solid at that temperature. Ions and Ionization Energy Today you are going to learn a little bit more about atoms and, in turn, the Periodic Table. You know that chemical reactions happen. You have seen fireworks exploding, wood burning, food baking and much more. The driving question here is “Why do chemical reactions happen?” To answer this question we will have to cover a few points: Point #1: Atoms react, and reactions happen, because atoms want to be “happy”. Here is what makes an atom happy: - Atoms are happy when they have a full outside energy level of electrons or 8 valence electrons. - Some atoms can be happy when they have ZERO electrons. The reason that this makes atoms “happy” is that when atoms have the outside energy level full or have 8 valence electrons they are the most stable. This is their lowest energy state. Point #2: Atoms gain or lose electrons in order to reach a state of “happiness”. Every atom wants to be just like the Noble Gases. To do this they need to gain or lose electrons. Atoms straight off of the Periodic Table have the same number of protons (+ charges) and electrons (- charges). The charges cancel out and the result is that all atoms on the Periodic Table are neutral or have no charge. Here is an example for you: Lithium has an atomic number of 3. This means that it has 3 protons (for an overall charge of “+3”) and 3 electrons (for an over-all charge of “-3”). When you add the charges together you get a net charge of zero (“+3” + “-3” = 0). As you can see, a lithium atom straight off the Periodic Table has no charge (it is neutral), but it is it “happy”? Well, according to the rules, it has to have a full outer energy level or 8 electrons in the outer energy level. Let’s look at the Bohr Model for Lithium: If you look at the model, you will notice two things: 1. Lithium has one electron in the outer energy level – it isn’t “happy”. 2. Lithium has a full inner energy level. If lithium wants to be happy, it has two options it can gain 7 electrons in order to fill up the outside energy level or it can lose the one electron that it has in the outer level and then it will be left with just its inner energy level which is full. What will lithium do? Will it lose 1 electron or gain 7 more electrons? To answer that question we need to get to Point #3. Point #3: Atoms are ‘lazy”. Atoms will do the least amount of work possible (this reminds me of some students that I know). Lithium is faced with the decision of losing one electron or gaining 7 new ones. Being lazy, it will go with losing one electron. When it does that, you get a Bohr Model that looks like this: Lithium has two electrons in the outside energy level and, since it is the first energy level which only can hold 2 electrons, lithium is, by definition, happy. When you look at the model above, you will note that the happy lithium has a “+” sign by it. That is because the lithium atom is charged now – it has become an ion and that leads us to Point #4. Point #4: Ions are charged atoms. Let’s look at lithium before it was happy (right off the Periodic Table) and after it became happy (when it lost the electron). Before: Lithium has 3 protons (+3 charge) and 3 electrons (-3 charge). The over-all charge of the atom is zero (“+3” + “-3” = 0). After: Lithium still has 3 protons (+3 charge), but now it only has 2 electrons (-2 charge). The over-all charge is +1 (“+3” + “-2” = +1). Practice Problems 1. For each of the elements listed on the table below, write down how many valence electrons it has, what it could do to become happy, what it will do to become happy and what charge ion it will form. Element Valence What it could do Electrons to become happy Lithium 1. Gain 7 electrons 1 2. Lose 1 electron Beryllium 1. Gain 6 2 2. Lose 2 Boron 1. Gain 5 3 2. Lose 3 Carbon 1. Gain 4 4 2. Lose 4 Nitrogen 1. Gain 3 5 2. Lose 5 Oxygen 1. Gain 2 6 2. Lose 6 Fluorine 1. Gain 1 7 2. Lose 7 Neon 1. Gain 0 8 2. Lose 0 Hydrogen 1. Gain 1 1 2. Lose 1 Francium 1. Gain 7 1 2. Lose 1 Iodine 1. Gain 1 7 2. Lose 7 What it will do to Ion Charge become happy (Show work!) Lose 1 electron #P + #E (+3) + (-2) = +1 Lose 2 electrons (+4) + (-2) = +2 Lose 3 electrons (+5) + (-2) = +3 Gain 4 electrons Lose 4 electrons (+6) +(-10) = -4 (+6) + (-2) = +4 (+7) + (-10) = -3 (+8) + (-10) = -2 (+9) + (-10) = -1 (+10) + (-10) = 0 (+1) + (-2) = -1 (+1) + (-0) = +1 (+87) + (-86) = +1 (+53) + (-54) = -1 Gain 3 electrons Gain 2 electrons Gain 1 electron Nothing Gain 1 electron Lose 1 electron Lose 1 electron Gain 1 electron 2. On the table below, fill out how each type of atom typically becomes an ion: Type of Element Metals Non-metals Metalloids Become ions by …….. Losing electrons Gaining electrons Gaining or losing electrons 3. What is so special about the elements in the Carbon Family? They can either gain or lose electrons. 4. Hydrogen can do two things to become “happy”. Based upon that, what other column on the Periodic Table could Hydrogen be placed in? Column #7 (since it can form an ion with a charge of “-1”). Alright, so now you know that atoms want to be “happy” and what atoms will do to become “happy”. Some atoms gain electrons and others lose them. Some atoms will do either. This leads us to a new property of atoms to learn about and a new trend to discover on your Periodic Table: First Ionization Energy First ionization energy is defined as the amount of energy that it would take to remove one valence electron from an atom. Based upon what you have learned about atoms and ions so far, it is time to make a prediction. Prediction (circle your choice in the sentence below) Atoms that gain/lose electrons will have the highest first ionization energies. Why did you make the choice that you made? Graphing First Ionization Energy Use the Periodic Table provided below to make the following graphs. Graph #1: First Ionization Energy vs. Atomic Number for Elements 1-20 1. What is the trend for first ionization energy as you go across a period? It increases. 2. Why do you think it does this? Going across a row/period, you go from atoms that want to lose electrons (metals) to atoms that want to add on more electrons. It makes sense that an atom that wants to get rid of electrons wouldn’t hold on to them as tightly as an atom that needs to gain electrons to become stable. Graph #2 First Ionization Energy vs. Atomic Number for Groups 1&2 First Ionization Energy vs. Atomic Number for Groups 1 & 2 1400 1200 Ionization Energy 1000 800 Column 1 600 Column 2 400 200 0 1 2 3 4 5 6 7 3. What is the trend for first ionization energy as you go down a group? It decreases. 4. Why do you think it does this? Each time you go down a column, you are adding an extra energy level. The attraction between the nucleus and the electrons decreases as they move away from each other. 5. How might first ionization energy help you explain why the atomic radius (yesterday’s trend) of the atoms decreases as you go across a period? 6. Atoms that gain electrons in order to become “happy” (get a full outer energy level or have 8 electrons in the outer level) tend to hold on to their electrons tighter. They pull them closer to the nucleus and that make sit harder to pull them away.