1. Practice 1. Write the ion formed by these element. a. a. iodine I -1 d. cobalt (II) Co +2 b. potassiumK +1 e. gallium Ga +3 c. sulfurS -2 f. chromium (III) Cr +3 ION FORMATION group “B” elements

2. Writing Ions Practice

3. IONOxidationCation Number or Anion Bromine1Anion Rubidium1Cation Barium2Cation Sulfur2Anion Tin (IV)4Cation Iodine1Anion Argon0Neither Aluminum3Cation Magnesium2Cation

4. IONOxidationCation Number or Anion Strontium2Anion Lead (II)2Cation Antimony (V)5Cation Phosphorus3Anion Copper (I)1Cation Selenium2Anion

5. Binary Compounds with Polyatomic Ions Covalently-bonded groups of atoms that behave as a unit and carry a charge Covalently-bonded groups of atoms that behave as a unit and carry a charge NO 3 -1 NO 3 -1

6. Covalent Bonds NH 3 Lewis Dot N H H H

7. Covalent Bonds NH 3 Energy Level H H H N

8. Covalent Bonds Ionic vs. Covalent Properties Covalent BondsIonic Bonds type of elementsNonmetals onlyMetals and Nonmetals type of bondingshare electronstransfer electrons structurenot rigid – solid, liquid or gas crystalline melting pointlowhigh hardnesssoft  hardvery hard conduct electricity? noyes (when dissolved in water)

9. Covalent Bonds: Diatomic Atoms There are 7 elements that can form covalent bonds between its atoms Hydrogen Atoms Molecule H· ·H H:H H· ·H H:H

10. Covalent Bonds: Diatomic Atoms NitrogenAtoms · · : N · · N : · · · · : N · · N : · · Molecule Forms a triple bond : N : : : N :

11. Covalent Bonds: Diatomic Atoms ·· ·· O : : O ·· ·· ·· ·· : F : F : ·· ·· ·· :Cl : Cl : ·· ·· ·· : Br : Br: ·· ·· ·· ·· : I : I : ·· ·· OXYGEN (Double bond between atoms) FLOURINECHLORINEBROMINEIODINE

12. Determine ionic or covalent bonds N 2 O 5 A liquid at toom temp PbNO 3 Covalent (nonmetals) Covalent (liquid) Ionic (Metal with nonmetal)

13. Determine ionic or covalent bonds A salt that conducts electricity in solution KFAgCl Ionic (conducts electricity) Ionic (metal with nonmetal) Ionic (Metal with nonmetal)

14. Determine ionic or covalent bonds Gasoline PCl 3 O 2 Covalent (liquid) Covalent (metal to metal) Covalent (share electrons)

15. Naming Covalent Compounds Oxidation numbers are not used in determining the formula unit Two nonmetals can combine in more than 1 way We use prefixes to name and indicate the number of atoms of each type

16. Naming Covalent Compounds PrefixNumber mono1 di2 tri3 tetra 4 penta5 hexa6 hepta7 octa8 nona9 deca10

17. Naming Covalent Compounds Write the name of the element that is farthest left first Write the other element second and change the ending to –ide Add prefixes to the two elements Do not use mono on first element

18. Naming Covalent Compounds CO 2 Element to left first, then the second element with an –ide ending Carbon Oxide Add prefixes Monocarbon Dioxide Drop Mono from first element Carbon dioxide

19. Naming Covalent Compounds CF 4 Element to left first, then the second element with an –ide ending Carbon Flouride Add prefixes Monocarbon Tetraflouride Drop Mono from first element Carbon Tetraflouride

20. Naming Covalent Compounds SiCl 3 Element to left first, then the second element with an –ide ending Silicone Chloride Add prefixes Monosilicone trichloride Drop Mono from first element Silicon Trichloride

21. Naming Covalent Compounds CO 2 Element to left first, then the second element with an –ide ending Carbon Oxide Add prefixes Monocarbon Dioxide Drop Mono from first element Carbon dioxide

22. Naming Covalent Compounds CO 2 Element to left first, then the second element with an –ide ending Carbon Oxide Add prefixes Monocarbon Dioxide Drop Mono from first element Carbon dioxide

23. Naming Covalent Compounds H2OH2OH2OH2O Element to left first, then the second element with an –ide ending Hydrogen Oxide Add prefixes Dihydrogen oxide Drop Mono from first element Dihydrogen oxide

24. Naming Covalent Compounds Common names to remember H 2 O = Water NH 3 = Ammonia CH 4 = Methane

25. Writing Formulas for Binary Covalent Compounds List the symbol of the first element in the name first and then second element next Use the subscripts to identify the prefix in the name for that atom

26. Writing Formulas for Binary Covalent Compounds Carbon Tetrachloride C Cl Tetra= 4 CCl 4

27. Writing Formulas for Binary Covalent Compounds Dinitrogen Trioxide NO NO Di = 2Tri = 3 N2O3N2O3N2O3N2O3

28. Writing Formulas for Binary Covalent Compounds Iodine Pentaflouride I F Penta = 5 IF 5

29. Writing Formulas for Binary Covalent Compounds Hexaboron Silicide B Si B Si Hexa = 6 B 6 Si

30. Writing Formulas for Binary Covalent Compounds Diantomny Pentoxide Sb O Sb O Di = 2Penta = 5 Sb 2 O 5

31. Writing Formulas for Binary Covalent Compounds Ammonia NH 3

32. Polar Covalent Bonds A type of covalent bond where electrons are shared unequally between atoms Electrons spend more time with one atom than the other The stronger atom will be slightly negative and the other will be slightly positive

33. Polar covalent Bonds Water: the electrons hang around the oxygen atom more than the hydrogen atom Example of Polar Covalent Bond in Action