Drill pd 3 11/17/14 Rank in order of increasing ionization energy. Si, C, S, F, Ca Rank in order of decreasing atomic radii. F, S, N Rank in order of increasing atomic radius As, Te, P, Al Rank in order of increasing electronegativity. Ge, P, As, Cs HINT: Look at group trends first, then period trends Answers Ca, Si, S, C, F F, N, S P, Al, As, Te Cs, Ge, As, P Drill 4A/4B
18/2014 11/17& Differentiate between ionization energy and electronegativity. What types of periodic trends are you noticing for atomic radius, ionization energy and electronegativity? Ionization energy is the energy needed to REMOVE one of the atoms outermost electrons while an atoms electronegativity is its ability to ATTRACT electrons to itself in a chemical Announcement Conclusions have been graded. You have one week to turn back into me for credit. PBIS stuff SWBAT: Analyze the trends of ionization energy, electronegativity and atomic radius by completing a graphing activity. Homework
-2 Review and Reinforcement pd 4A and 4B Graph PERIODIC TRENDS GRAPHING ACTIVITY GRAPH DATA Construct 1 graph for ionization energy, electronegativity and atomic radius. Answer questions on the Worksheet. Octet Rule Atoms tend to gain, lose, or share electrons so that each atom has a full outermost energy level, which typically consists of 8 electrons (called an octet) Periodic Table Patterns Nuclear Charge Nuclear charge-the charge in the nucleus or the number of protons Across increases Down increases Atomic Mass
Weighted average (based on mass and percent abundance of each naturally occurring isotope) Across increases Down increases Remember there are some exceptions to this like Te and I Atomic Radius One-half the distance between the nuclei of identical atoms that are bonded together. Ionization Energy (IE) Ionization energy is the energy needed to REMOVE one of the atoms outermost electrons Electronegativity An atoms electronegativity is its ability to attract electrons to itself in a chemical bond Trend for Atomic Radius Atomic radius decreases as you go from the left to the right across a period. This is because there is an increased nuclear charge (protons) but no additional shielding electrons
come between valence electrons and nucleus. Atomic radius increases as you go down a group. Increased distance of electrons and additional electron energy Shielding Effect The shielding effect is the Nucleus reduction of attractive force between the nucleus (+) and its outer electrons (-) due to the Shielding electrons blocking affect of the inner Valence electrons shielded by inner electrons electrons Snowman analogy Trend for Ionization Energy Ionization energy increases as you go from the left to the right across a period this means its MORE DIFFICULT to remove an electron because of increased positive nuclear charge. Ionization energy decreases as you go down a group this means its EASIER to remove an
electron because as atomic radius increases, outermost electrons are further away from nucleus. Trend for Electronegativity Electronegativity increases as you go from the left to the right across a period Electronegativity generally decreases as you go down a group in the periodic table ** Because the noble gases form very few compounds, they do not have an electronegativity value. Trend for Electronegativity (cont) The highest electronegativity values are located in the upper-right hand corner of the periodic table Fluorine has the highest electronegativity value of 4.0 The lowest electronegativity values are located in the lower-left hand corner of the periodic table It is NOT an amount of energy Ionization Energy (IE) review
Ionization energy this is the energy needed to remove one of the atoms outermost electrons Metals have low IE Nonmetals have high IE Trend for IE 1) IEs decrease as you move down a group why? Why? The electrons in larger atoms are held less strongly by the nucleus, therefore as you move down a group, the IE decreases Trend for IE 2) IEs increase as you move from the left to the right across a period why? WHY? As you move across a period, there is a decrease in atomic radius, therefore causing the IE to increase Removing electrons from positive ions
With sufficient energy, electrons can be removed from positive ions. The energy required to remove a second electron from an atom is called its second IE, and so on The second IE will be greater than the first IE, the third IE greater than the second, etc. because as electrons are removed, fewer electrons remain to shield the attractive nuclear force. Electron Affinity (EA) Neutral atoms can acquire electrons. An atoms electron affinity is the energy change that occurs when an electron is acquired by a neutral atom. Trend for EA They change in irregular ways across a period and down a group General rules: nonmetals have higher electron affinities than do metals (this means its usually easier to add an electron to a nonmetal) The halogens gain electrons most readily higher electron affinities. Trends Across the Periodic Table
Shielding Effect Stays the Same Atomic Radius decreases Ionization Energy Increases Electronegativity Increases PERIODIC TABLE OF THE ELEMENTS 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16
17 18 1 2 H He 1.008 3 4 5 Li Be 6.941 11 9.012 12 6 7 8 B C N O
F Ne 12.01 14 14.01 15 16.00 16 19.00 17 20.18 18 Al Si P S 22.99 19 26.98 31 28.09 32 30.97 33
32.07 34 21 22 K Ca Sc Ti 39.10 37 40.08 38 44.96 39 Rb Sr 85.47 55 87.62 56 Cs Ba 132.9 87 137.3 88 Fr Ra 
51 78.96 52 Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te 91.22 72 92.91 73 178.5 104 180.9 105 Cl Ar 35.45 35 39.95 36 Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr 52.00 42 95.94 74 [98.9] 75 101.1 76 Lu Hf Ta W Re Os 175.0
103 27 4.003 10 10.81 13 Na Mg 24.31 20 9 183.8 106 186.2 107 190.2 108 102.9 77 Ir 192.2 109 Lr Rf Db Sg Bh Hs Mt 106.4 78 107.9 79
112.4 80 114.8 81 118.7 82 121.8 83 127.6 84 79.90 53 83.80 54 I Xe 126.9 85 131.3 86 Pt Au Hg Tl Pb Bi Po At Rn 195.1 110 197.0 111
70 La Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb 138.9 89 140.0 90 140.9 91 Ac Th Pa  Version Date 29 February 2000 232.0 231.0 144.2 92  93 150.4 94 152.0 95 157.3 96 158.9 97
162.5 98 164.9 99 167.3 100 168.9 101 173.0 102 U Np Pu Am Cm Bk Cf Es Fm Md No 238.0           Shielding Effect Increases
Atomic Radius Increases Ionization Energy Decreases Electronegativity Decreases Drill 11/19/14 Ignore sizes of atoms: Comparison of Na and Cl atoms 1. Both atoms are in the same period. Explain the differences in their sizes. 2. 3. 4. Predict the charge that an ion of each would have. Explain your answer. Compare the ionization energy required to remove the first electron from each of these atoms. Draw the ion for each atom. Make sure to represent their sizes relative to their original sizes. Answers to Drill 1. 2. 3. 4. Cl is smaller than Na because the increased
positive nuclear charge exerts a stronger pull on the e- shrinking the cloud. A Na ion would have a charge of +1 and Cl ion, a charge of -1 because Na must lose an e- to have a full octet and Cl must gain an e-. The IE of Cl would be higher because nonmetals hold on to their valence e- more tightly. The Cl ion is now larger than the Na ion. Sodium lost its outermost orbital. The positive nuclear charge is felt more strongly.
Weak Nuclear Force. arise in certain radioactive processes. 10-8. Very very short! At the atomic level - all contact forces are result of repulsive electromagnetic forces - the repulsion of atoms' electric fields. Field Forces. How to Solve Force Problems.
(b) Obliterated or otherwise removed from the document, by any method, including, without limitation, through the use of computer software… University Administrative Manual Section 64 gives additional detail regarding university departments that are authorized to collect and maintain social security...
British Literature. Frankenstein Take Home Essay. ... The next 5 slides are review from the Macbeth essay… Argument (Thesis) Using Text as Evidence. Whenever you make a claim, it should be supported by either implicit or explicit textual evidence.
Shown below is a model for a transcribed strand of RNA. Fig. 14-3d, p.221 Termination unit of transcription in a DNA strand exon intron mature mRNA transcript poly-A tail snipped out snipped out exon exon intron cap transcription into pre-mRNA...
Community and Disability - What it has Meant. You are only part of a disability community as services control your life and the people you spend time with and the places you spend time in (This is a segregated community...
Chapter 12 Race And Ethnicity Key Terms Ethnic groups A social category of people who share a common culture. Racialization A process whereby some social category such as social class or nationality takes on what are perceived in the society...