CH301 Vanden Bout/LaBrake Fall LM18 Posted DUE TH 9AM Study Ionic and Covalent Bonding and Nomenclature on Fundamentals Nomenclature Quiz Th

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1 Unit2Day4-VandenBout Page 1 Unit2Day4-VandenBout Monday, September 30, :30 PM Vanden Bout/LaBrake/Crawford CH301 ELECTRON CONFIGURATION and BONDING Where did all that salt come from? UNIT 2 Day 4 Important Information LM18 Posted DUE TH 9AM Study Ionic and Covalent Bonding and Nomenclature on Fundamentals Nomenclature Quiz Th Laude LM Lecture 7 CH301 Vanden Bout/LaBrake Spring 2013

2 What are we going to learn today? Electron Configuration and Bonding Relate the valence shell electron configuration to bonding Understand the similarities and differences between ionic and covalent bonding Recognize and name compounds based on elemental composition QUIZ: CLICKER QUESTION 1 The trend on the periodic table is that atomic radii: a) Increases as you move from L to R across b) Decreases as you move from R to L across c) Increases as you move from T to B down d) Increases as you move from B to T up e) Both b and c QUIZ: CLICKER QUESTION 2 Which of the following symbols does not match the elemental name? A.Fe - Iron B.As Arsenic C.Co Copper D.Sn Tin Unit2Day4-VandenBout Page 2

3 match the elemental name? Unit2Day4-VandenBout Page 3 A.Fe - Iron B.As Arsenic C.Co Copper D.Sn Tin E.V - Vanadium QUIZ: CLICKER QUESTION 3 At the end of the last class period we saw a demo. Two metals were tossed into water and something happened. a)the metals sank to the bottom of the bucket b)the metals floated in the bucket c)the metals spun around the surface of the water and then burst into flames d)this is not true, just a trick question for the 75 people who were absent Thursday

4 Unit2Day4-VandenBout Page 4 Where are the electrons in Ne? 1s 2 2s 2 2p 6 very stable gas Z=10 Where are the electrons in Na? [Ne]3s 1 not so stable metal Z=11 Where are the electrons in K? [Ar]4s 1 more, not so stable metal Z=19 Shielding and Effective Nuclear Charge Left to Right Z eff is increasing Top to Bottom Z eff is similar Top to Bottom. Electron in higher in Energy. Farther from the nucleus THIS CAN EXPLAIN A LOT ABOUT THE PERIODIC TABLE Trend: Atomic Radii

5 Atomic Radii Unit2Day4-VandenBout Page 5 CH302 Vanden Bout/LaBrake Fall 2012 EXPLAIN SPIKE IN IONIZATION ENERGY! CH302 Vanden Bout/LaBrake Fall 2013

6 Unit2Day4-VandenBout Page 6 Based on this trend in ionization energies this element is A. argon B. carbon C. magnesium D. sulfur SHOW SOME ELECTRON CONFIGURATIONS OF IONS

7 2Na(s) + Cl (g) Unit2Day4-VandenBout 2NaCl(s) Page 7 CH302 Vanden Bout/LaBrake Fall 2012 POLL: CLICKER QUESTION 4 Where did this guy get all of that salt (NaCl)? a)it formed from Na + and Cl - ions in the water b)he first pitch a few block of Na metal into a pool and then bubbled in Cl 2 gas. c)he add the Cl 2 gas to the water that already had Na + ions. d)he added Na metal to the water that already had Cl - ions. ELECTRON LEAVES.. WHERE DOES IT GO? Metals tend to give up electrons to nonmetals, in each case the valence is satisfied Sometimes is complicated eg in the sodium in water demo Sometimes is more obvious

8 Unit2Day4-VandenBout Page 8 Sometimes is complicated eg in the sodium in water demo Sometimes is more obvious 2Na(s) + Cl 2 (g) 2NaCl(s) Sometimes they are already gone! Formation of Ionic Compound Downhill in Energy Ionic Compound downhill in energy..

9 Unit2Day4-VandenBout Page 9 Ionic Compounds Not a discrete pair of ions it is a whole collection POLL: CLICKER QUESTION 5 Coulomb s Law Lattice energy depends on Coulomb s Law and the crystal structure (the way the ions are packed together). Assuming the same crystal structure, which do you think would have the larger lattice energy: a)naf b)nabr? Ionic Radius

10 Unit2Day4-VandenBout Page 10 Polyatomic Ions Calcium Carbonate Ca 2+ CO 3 2- Know the names and formulas for all the common polyatomic ions. See the Data & Tables under more on the ebook

11 Unit2Day4-VandenBout Page 11 POLL: CLICKER QUESTION 6 Naming Ionic Compounds Choose the formula that corresponds to: sodium oxide a)nao b)nao 2 c)na 2 O d)na 2 O 2 Naming Ionic Compounds You need to be able to name common ionic compounds and with elemental ions and polyatomic ions. WEBSITE FUNDAMENTALS DO THE WORKSHEETS What about compounds that aren t ionic.. Covalent? How are they formed? Are electrons lost???? No.. They are shared (two non-metals two elements with similar electronegativities)

12 Unit2Day4-VandenBout Page 12 No.. They are shared (two non-metals two elements with similar electronegativities) Covalent Compounds Characterize the bond. Bond Length Bond Strength Electron Pair Shared Equally? YES PURE COVALENT NO POLAR COVALENT SHOW THE SIMULATOR..

13 Unit2Day4-VandenBout Page 13 Electronegativity-electron pulling power of an atom when it is part of a molecule When one atom is more electronegative than another in a bond, a polar covalent bond is formed. Degree of polarity is dependent on difference in electronegativities.

14 Unit2Day4-VandenBout Page 14 Ionic vs Covalent Bonds All bonds can be viewed as hybrids between purely ionic and purely covalent When two identical atoms are bound, it is purely covalent. When two different atoms are bound, one may have a greater attraction for electrons, and have a partial negative charge. Polar covalent bond degree is measured as dipole moment When one atom has a much stronger attraction to the electrons than the other, an electron may be donated yielding an ionic bond. Covalent Compounds - Naming

15 Unit2Day4-VandenBout Page 15 Covalent Compounds What is attached to what? Valence electrons Lewis symbols Lewis Structure Satisfy the Octet H 2 CH 4 What have we learned? NUCLEAR CHARGE FELT BY VALENCE ELECTRONS IS SHIELDED BY THE CORE ELECTRONS ATOMS BEHAVE IN CERTAIN PREDICTABLE WAYS WHICH CAN BE CORRELATED TO THE ELECTRON CONFIGURATIONS IONIC BONDS TEND TO FORM BETWEEN METALS AND NONMETALS COVALENT BONDS TEND TO FORM BETWEEN NONMETALS AND NONMETALS NAMING COMPOUNDS IS IMPORTANT AND NECESSARY

16 Unit2Day4-VandenBout Page 16 Learning Outcomes Identify metals and non-metals and predict types of compounds (ionic/covalent) Between different elements Relate coulombs law and lattice energy Name basic binary ionic compounds including polyatomic ions Name basic covalent compounds containing two elements Explain the trends in electro-negativity on the periodic table Differentiate between pure covalent and polar covalent bonds