1. Chemical Bonds Chapter 20

2. Sec. 1 - Combined Elements Elements make  ________________ Properties of compounds are different from ______________ Ex: Sodium Chloride, __________ (table salt) –Na: silver, metal, reacts violently w/ _____ –Cl: _______________ greenish-yellow gas

3. Chemical Formulas H 2 O  ___ atoms H and 1 atom O

4. Atomic Stability Why do atoms form compounds? To be ______________ Why don’t noble gases form compounds? Stable!  __________ energy levels!! All atoms form compounds to get FULL ________________ LEVELS  stable

5. Atomic Stability

6. 1 st energy level full with ______ e - Other levels full with ______ e -

7. Stability is Reached NaCl is made from atoms ___________ or gaining electrons H 2 O is different  elements _________ electrons Both ways make a… Chemical ______________: force that holds atoms together in a compound

8. Types of Bonds Section 2

9. Ionic Bonds Atoms can lose or ____________ e - to make an ion ____________: a charged particle because it now has either more or fewer e - than p + ______ charge: if fewer e - than p + ______ charge: if more e - than p +

10. Calcium Oxide - CaO Calcium has __ valence e - ___________ 2 e - and becomes an ion Ca +2 Oxygen has __ valence e - ____________ 2 e - and becomes an ion O -2 Calcium ___________ e - to Oxygen Opposite charges ATTRACT!!

11. Ionic Bond – Metal and Nonmetal Def: the force of attraction between ________________ charges of the ions Ex: MgCl 2 – ___________ net charge Smallest Particle = formula _________

12. Covalent Bond – 2 Nonmetals Def: attraction between atoms when they _____________ electrons Smallest particle = ______________ H 2 O CO 2 N 2

13. Covalent Bonds Single Covalent Bond: ______ shared electrons Multiple Bonds: –Double (____ shared e - ) –Triple (_____ shared e - )

14. Naming Compounds Section 3

15. Naming Ionic Compounds Binary compound: has ____ elements Ionic compounds – name of _______ makes name of compound ____________ Ions: name of element –Na + = Sodium ion Negative ions end in – _________ –Cl - = Chloride ion

16. Special Ions

17. Polyatomic Ions

18. Sec. 3 – Writing Formulas Remember… compounds are __________________!! 1.Write the (_____) ion 2.Write the (_____) ion 3._____________ charges: criss-cross method ______________ to smallest whole #s

19. Write the Formula Lithium Nitride Lead(IV) Phosphide Calcium Fluoride Ammonium Phosphate Magnesium Hydroxide

20. Naming Ionic Compounds Put the two ion names together! NaCl –Na + = _____________ ion –Cl - = ______________ ion – Sodium Chloride

21. Practice Naming RbCl Mg 3 N 2 AlF 3 CrCl 3 Ca(OH) 2 Na 2 CO 3 NH 4 Cl

22. Naming Covalent Compounds _______ ions involved Same ______________ can make different compounds: CO, CO 2 Naming: Use ______________ to tell how many atoms of each element Second element ends in -_________ Prefix ___________ is left out with the first element

23. Prefixes

24. Practice Naming N 4 O 6 C 2 O 5 PH 3 Sulfur Hexafluoride Dihydrogen Monoxide

25. Hydrates Def: has water chemically attached to its ions CoCl 2 6H 2 O ___________________________ CaSO 4 2H 2 O ___________________________