1. Warm Up Iron can form two different oxides ….. Fe 2 O 3 and FeO. We know for absolute certainty that an oxygen anion always has a -2 charge. What is going on here … how can there be two iron oxides???

2. Warm Up-Answer -Turns out we need to balance charges such that compound has zero charge -So in FeO if we have 1 oxygen atom that is always a -2 charge then (1 O atom)(-2) = -2 ….. so then our Fe must have a +2 charge to balance out (1 Fe atom)(+2) = +2 …. +2 and -2 cancel out -With Fe 2 O 3 we have (3 O atoms)(-2) = -6 So (2 Fe)(???) = +6 The answer is of course +3 ….

3. Warm Up - Answer FeO has a +2 charged iron cation Fe 2 O 3 has a +3 charged iron cation

4. Ion Formation and Naming Ions Chapter 7.1/9.1

5. Learning Objectives You will know what valence electrons are and how to determine how many. You will be able to draw electron dot structures of 1A-8A elements You will understand the octet rule and how it leads to stable cations and anions You will learn how to name simple anions and cations You will understand how to name transition metals and polyatomic ions

6. Valence Electrons –Electrons in the highest occupied energy level (s and p only) –Determines chemical properties of element –Equals the group number (A series) –Involved in chemical bonding

7. Lewis Dot Structures –Diagrams that show the valence electrons of an atom using dots –Also called electron dot structures

8. Octet Rule – Atoms tend to gain, lose, or share electrons until they are surrounded by eight valence electrons – Goal to be isoelectronic to a noble gas

9. Special Vocabulary  Isoelectronic –Ions that have the same electron configuration  Halide ions –When the halogen group elements become ions (F -, Cl -, Br -, I - )

10. Monoatomic Ions  Single atom with a positive or negative charge. Occurs when lose (cation) or gain (anion) valence electrons 1A2A3A4A5A6A7A8A Li + Be 2+ B 3+ N 3- O 2- F-F- Na + Mg 2+ Al 3+ P 3- S 2- Cl - K+K+ Ca 2+ As 3- Se 2- Br - Rb + Sr 2+ I-I- Cs + Ba 2+

11. Naming Cations  Naming of cation usually involves the name of the element plus the word ion Na + would be called sodium ion –Alternative techniques for variable charge ions (transition elements)

12. Naming Transition Metal Ions SymbolModern name Cu + Copper(I) ion Cu 2+ Copper(II) ion Fe 2+ Iron(II) ion Fe 3+ Iron(III) ion Sn 2+ Tin(II) ion Sn 4+ Tin(IV) ion A few transition metals only have one charge and roman numerals are not used … Ag +, Cd 2+, Zn 2+

13. Naming Anions  Naming of anion –Monatomic anion ends in –ide Not chlorine … chloride Not oxygen … oxide Not nitrogen … nitride –Many anions are polyatomic – need to memorize the more common ones … chart I gave you today.

14. Polyatomic Anions Ions that are composed of more than one atom. Most are anions (negative charge). SO 4 2- sulfate The names of most polyatomic anions end in –ite or –ate.

15. Homework Chapter 7.1 (Read!!) page 193 (#3-9) page 207-208 (#31,32, 62) Chapter 9.1 (Read!!) page 258 (#4,5,8,9) page 281 (#42-46)