1. Naming and Writing Ionic Compounds

2. Ionic Compounds Occur between a metal and non-metal Occur when electrons are transferred between atoms forming ions Metals make cations = positive ions Nonmetals make anions = negative ions Also use these rules when a polyatomic ion is present

3. Ionic Bonding Using Lewis Dots In ionic bonding, electrons are transferred Na + Cl Cl + Ca K + F Mg + I Be + S Na + O Al + Br

4. Writing Ionic Compounds

5. 5 Guide to Writing Formulas from the Name Copyright © 2005 by Pearson Education, Inc. Publishing as Benjamin Cummings

6. 1. Identify the Ions Look at the group they are in on the periodic table Determine the type of ion created and assign an oxidation number (charge) BeBr Group 2 Group 7 2 electrons7 electrons Be +2 Br -

7. 2. Criss-Cross Charges Criss-Cross Charges Drop Signs Do not write any “1’s” Be +2 Br - Be 1 Br 2 BeBr 2

8. 3. Reduce/Simplify Reduce any subscripts to the simplest form or simplest ratio. LiBr 2 is already simplified But copper(II) oxide needs to be reduced since 2:2 atoms is the same as 1:1. Cu +2 O -2  Cu 2 O 2  CuO

9. 9 Learning Check Write the formulas of the following ions: Br − S 2− N 3− Na + Al 3+

10. Other Things to Watch for… Roman Numerals – The numeral in the parenthesis is the charge – Only occur with Transition Metals – copper(II) oxide = Cu +2 O -2 Polyatomic Ions – Use the same rules – Place entire polyatomic ion in parenthesis when criss-crossing

11. Example Zinc(II) Hydroxide – Zn = Transition Metal = Zn +2 – OH = Polyatomic ion = (OH) - Zn +2 (OH) - Zn(OH) 2

12. 12 Learning Check What is the correct formula for each of the following? A. Copper(I) nitride 1) CuN2) CuN 3 3) Cu 3 N B. Lead(IV) oxide 1) PbO 2 2) PbO 3) Pb 2 O 4

13. Naming Ionic Compounds

14. Naming Ionic Compounds with Two Elements

15. 1. Identify the cation and anion Reverse Criss-Cross Al 2 S 3 Al +3 S -2

16. 2. Name the Cation Al +3 S -2 The cation is the positive ion Use its element name Al +3 = Aluminum

17. 3. Name the Anion Al +3 S -2 The anion is the negative ion Use the element name, but change the last part to -ide S -2 = Sulfur  Sulfide

18. 4. Put it together Cation name is first Anion is second Al 2 S 3 Al +3 S -2 Aluminum Sulfide

19. 19 Write the names of the following compounds. 1) CaO___________ 2) KBr___________ 3) Al 2 O 3 ___________ 4) MgCl 2 ___________ Learning Check

20. 20 Write the names of the following compounds: 1)CaOcalcium oxide 2)KBrpotassium bromide 3)Al 2 O 3 aluminum oxide 4)MgCl 2 magnesium chloride Solution

21. Other Things to Watch for… Roman Numerals – Needed if contains a transtition metal – Write in parenthesis after element name – Cu +2 O -2 = copper(II) oxide Polyatomic Ions – Use the same rules – Name polyatomic by its name

22. Example: Pb = Lead (a transition metal) NO 3 is a polyatomic ion Pb(NO 3 ) 2 Pb +2 NO 3 -1 Lead (II) Nitrate

23. 23 Learning Check Select the correct name for each. A. Fe 2 S 3 1) iron sulfide 2) iron(II) sulfide 3) iron(III) sulfide B. CuO 1) copper oxide 2) copper(I) oxide 3) copper(II) oxide

24. 24 Solution Select the correct name for each. A. Fe 2 S 3 3) iron (III) sulfide Fe 3+ S 2- B. CuO 3) copper (II) oxide Cu 2+ O 2-

25. 25 Learning Check What is the correct formula for each of the following? A. Copper(I) nitride 1) CuN2) CuN 3 3) Cu 3 N B. Lead(IV) oxide 1) PbO 2 2) PbO 3) Pb 2 O 4

26. 26 Solution The correct formula is A. Copper (I) nitride 3) Cu 3 NNeed 3Cu + and N 3- B. Lead (IV) oxide 1) PbO 2 Need Pb 4+ and 2O 2-