1. Ch. 7 Bonding
7.2ish
Types of Bonds

2. Metal(M), Nonmetal(NM), Semi- metals (SM)

3. Ionic Bonds Atoms gain or lose electrons to form charged ions.
+/- attraction creates electrostatic attraction to form bond
Recognize by Metal with a Nonmetal (M/NM)
Ex: NaCl AlBr3 MgSO4 NH4Cl
Ionic Compounds are also called salts

4. Metallic Bonds
Metallic bonds explain why metals have the properties they have (shiny, etc)
Bonds can occur within an element or Alloy
Alloy is a mixture of 2 or more metals
Stainless steel, bronze, brass, etc.
In metallic bonds v.e. are mobile (like a “sea” of e-. V.E. can float between atoms.

5. Covalent or Molecular Bonds
Atoms share v.e. to obtain octet rule.
Covalent bond or molecular bond (interchangeable)
Recognize by Nonmetal and Nonmetal (NM/NM)
Ex: CO NH H2O
Biological Molecules are covalent
Ex: C6H12O amino acids
Diatomic molecules are covalent (N2, O2, F2, Cl2, Br2, I2)

7. Ionic Compounds Properties
Most are crystalline solids at room temp.
High melting and boiling points
They are electrolytes (conduct e- in water)

8. Molecular Properties Tend to be liquids or gases at room temp.
Lower melting/boiling point than Ionic
Non-electrolytes (doesn’t conduct e- in water)
Some elements tend to be Diatomic
Diatomic elements come in pairs when not in compound
“Scared 7” N2, O2, F2, Cl2, Br2, I2, H2

9. Element
Ion formula and charge
Ion name
Lewis dot structure of atom
# of valence e- in atom
Cation or anion?
Tin-lost 2 e- X
Potassium
nitrate
Chlorine
Manganese
(lost 1 e-)
Zinc
sulfite
Sulfur
Phosphorus
Cyanide
Ammonium
Strontium
Iron
(lost 3 e-)
Silver
Aluminum
Fluorine
Calcium
acetate
Copper
(lost 2 e-)
Carbonate

10. Ch. 7 Bonds
7.1 Recap of Ions

11. IONS Valence Electrons (v.e.): used in bonding
Group number = valence electrons
Cations: + ions; lose e-
Anions: - ions; gain e-
Polyatomic Ions: group of atoms with a charge
Octet Rule: compounds form so atoms can achieve a noble gas configuration (8 v.e.)

12. Ions on the Periodic Table

13. Naming Ions
Cations(group 1A,2A,3A): name element off P.T. and add “ion”
Mg+2 = Magnesium Ion
Anions: Name element off P.T. BUT change ending to “ide” then add “ion”
O-2 = Oxide ion
Transition Metals: have multiple charges (all +) so charge is represented by a Roman Numeral.
Mn+2 = Manganese II Ion; Mn+3 =Manganese III ion
Polyatomic Ions: groups of atoms w/ a charge
NO3- = nitrate *** memorize***

14. Group 1A,2A,3A (all cations): name only
*Group 1A,2A,3A (all cations): name only *Group 5A,6A,7A (all anions): end –ide Transition (cations): charge variable so Roman Numeral

16. Polyatomic Ions Most are anions Most have oxygen
They end in –ate, ite, occasionally -ide

17. Ion formula Ion Name LDS V.E. Cation or Anion? Lead: lost 4e- Sodium
Element
Ion formula
Ion Name
LDS
V.E.
Cation or Anion?
Lead: lost 4e-
Sodium
Iodine
Pb+4 X
Cation
Lead IV X
Na+ 1
Cation
Sodium I- 7
Iodide
Anion

18. Naming and Writing Ionic Compounds Ch. 7/9

19. Writing Formulas Charges must add up to 0; compounds are neutral
Write down ions with charges
Find common multiple so charges cancel
The multiplier becomes subscripts
Example:
Magnesium Iodide = Mg+2, I-
Common multiple is 2, so for Mg 1 is multiplier; for I- 2 is multiplier
Formula is MgI2

20. Your Turn Write formulas of the following ionic compounds:
Potassium sulfate
Zinc phosphide
Manganese II carbonate

21. Naming Ionic Compounds
Split compound into Cation/Anion (2 ions) Metal/Non-metal
Name cation using periodic table.
If representative (1A,2A,3A); just name
If transition: determine charge. Charge becomes Roman Numeral after name
Name Anion:
If representative (5A,6A, 7A), change ending to –ide
If polyatomic, name from memory
Put 2 ion names together (generally ONLY 2 names)

22. Example for Naming Ca(NO3)2 Ca NO3
Ca is representative so just Calcium
Anion is polyatomic = nitrate
Calcium Nitrate

23. Your Turn: Name:
AlCl3
Mn2O3
CdCl2
K2SO4