1. Chapter 8: Ionic Compounds
11/16/15

2. Objectives Students will be able to Define chemical bond
Related chemical bond formation to electron configuration
Describe the formation of positive and negative ions

3. 8.1: Forming Chemical Bonds
Chemical bond- the force that holds two atoms together
Form by the attraction btwn
+ nucleus and – e-
+ ion and a - ion
Ionic bonds- exist between oppositely charged ions
Cation- positively charged ion
Anion- negatively charged ion

4. Mini-review
Electron configuration reveals Principle Energy Level where valence electrons are found
Valence electrons are the electrons involved in bonding
Represent valence electrons via electron dot structures

5. Formation of Positive Ions
Positive ions form when atoms lose electrons in order to attain 8 valence electrons (like a noble gas)
Examples:
Na 1s22s22p63s1  1 val. e-
When sodium loses that one electron it assumes a noble gas config. of [He] 2s22p6
Once it ionizes it then has more protons than electrons and has a charge of +1. (CATIONS)

6. Formation of Negative Ions
Again, atoms want to attain 8 val e-
Example:
Cl: 1s22s22p63s23p5 will gain 1 e- to attain a tot. of 8
When chlorine gains that one electron it assumes a noble gas config. of s2p6
Once it ionizes it then has more electrons than protons and has a charge of -1. (ANIONS)

7. Charge Chart – write on your periodic table…no need to copy word for word here.
Group 1A  all will form +1 charge
Group 2A  all will form +2 charge
Group 3A  all will form +3 charge
Group 4A  +/- 4 charge
Group 5A  all will form a -3 charge
Group 6A  all will form a -2 charge
Group 7A  all will form a -1 charge
Group 8A  will not form a charge

8. 8.2 Formation of Ionic Bond
Ionic bond- the electrostatic force that holds oppositely charged particles together
Forms between positively charged metal cations and negatively charged non-metal anions.
Example:
Na+1 and Cl-1 becomes NaCl
1s22s22p63s1
3p53s2p62s21s2

9. Also explained via Electron Dot Models

10. Ionic Vocab.
If a metal combines with a non-metal it forms an ionic compound called a salt.
Exception: A metal bonding with oxygen is called an oxide.
Many ionic compounds are binary which mean they consist of two elements.

11. What happens if….
A compound forms from Calcium (Grp. 2A) and Fluorine (Grp. 7A)
Calcium will need to lose _2__ electrons to become stable.
Fluorine will need to gain _1_ electron to become stable.
SO, what happens?
One Ca+2 cation will attract two F-1 anions
CaF2

12. In-class Ex. page 217 7. Sodium and nitrogen 8. lithium and oxygen
9. strontium and fluorine
10. aluminum and sulfur
11. cesium and phosphorus

13. Properties of Ionic Compounds
Crystalline structure
Large amt. of energy required to break bonds
Formation of ionic bonds is always exothermic

14. Solid state non-conductors (ions fixed)
In aqueous solution  great conductors (aka electrolytes) (ions can move)

15. Energy
During any chemical reaction (rxn) energy is either absorbed or released.
Endothermic – when E is absorbed
Exothermic – when E is released
Formation of ionic compounds from + or – ions is ALWAYS exothermic

16. Lattice energy
The energy required to separate one mole of the ions of an IC
The strength of the forces holding ions in place is reflected by the lattice energy.
The more – the lattice E, the stronger the force of attraction.

17. 8.3 Names and formulas for ionic compounds

18. Bell Ringer – turn in
Write the ionic compound equation for when the following elements form an ionic bond:
Potassium and Iodide
Magnesium and Chloride
Aluminum and Bromide
Cesium and Nitride
Barium and Sulfide
Magnesium and Carbon
Rubidium and Oxygen

19. Objectives Students will be able to
Write formulas for ionic compounds and oxyanions
Name ionic compounds and oxyanions

20. 8.3 Names and Formulas for Ionic Compounds
Formula units
simplest ratio of the ions represented in an ionic compound
Overall charge (net charge) is ZERO
Ex. KBr [one ion of potassium (K) and one ion of Bromine (Br)]

21. Determining Charge Monotomic ions: single element ions
charge is equivalent to the group number (Group 1A-Group 4A)
Charge is called its oxidation number
Oxidation state equals the number of electrons transferred from an atom of the element to form the ion.
Transition elements can have more than one oxidation state (see page 222, table 8.5)

22. Polyatomic Ions- ions made up of more than one element.
The charge on polyatomic ions applies to the entire group of atoms
Acts as an individual ion rather than a group
Ex. NH4+1 and Cl-1
NH4Cl

23. Common Polyatomic Ions

24. Polyatomic Ions you will be responsible for memorizing
Ammonium
Nitrite
Nitrate
Hydroxide
Hydrogen carbonate
Chlorate
Bromate
Acetate
Carbonate
Sulfite
Sulfate
Peroxide
phosphate

25. Naming Compounds
With monotomic ions, cations stay the same; however, anions change their ending to –ide
Polyatomic ions:
Most are oxyanions (has oxygen)
Some are composed of exact same ions but in different amounts
The ion with more oxygen ends in -ate
The ion with less oxygen ends in –ite
Ex. NO3-1 nitrate NO2-1 nitrite

26. In-Class Ex. Page 225 24. Sodium and nitrate 25. Calcium and chlorate
26. Aluminum and carbonate
27. Potassium and chromate
28. Magnesium and carbonate

27. Chlorine (forms 4 oxyanions)
ClO4-1: perchlorate
ClO3-1:chlorate
ClO2-1: chlorite
ClO-1: hypochlorite

28. Rules in a Nutshell 1. Name cation before anion
2. Monotomic cations use the name
3. Monotomic anions use the root of the name and add –ide
4. Groups 1-2 metals have one oxidation number while transition metals have more than one
5. Polyatomic ions  name them.

29. Practice
8.3 on your worksheet packet

30. 8.4 Metallic bonds and properties of metals
8.4 Metallic bonds and properties of metals

31. Bell Ringer – Turn in – 11/18/15
Name each of the following ionic compounds:
K2O
CaCl2
Mg3N2
NaClO
KNO3
Give the formula for each of the following ionic compounds:
Calcium iodide
Silver (I) bromide
Copper (II) chloride
Beryllium hydroxide
Magnesium phosphate

32. 8.4 Metallic Bonds and Properties of Metals
Objectives:
Students will be able to
Describe a metallic bond
Explain the physical properties of metals in terms of metallic bonds
Define and describe alloys

33. 8.4 talks about when two or more metals combine.
RECALL:
IONIC BONDS
Occur between metals (cation) and nonmetals (anion)
Na (metal – cation) and Cl (nonmetal – anion)
NEW:
8.4 talks about when two or more metals combine.
METALLIC BONDS

34. METALLIC BONDS
When metals bond together, they don’t do so ionically like metals and nonmetals.
They create a sea of electrons
Electron sea model
E- move between all atoms – delocalized electrons

35. Very similar to a lattice structure
Metallic cation is formed when their valence e- move away from them.
Metallic bond is the attraction of metallic cations for delocalized e-.

36. Properties of Metals
It requires more energy to boil a metal than to melt it
b/c it has strong metallic bonds keeping atoms together

37. Properties of Metals Metals are malleable Hammered into sheets
Drawn into wires
Metallic bonds allow atoms to move past each other

38. Properties of Metals They’re durable
Even though the e- move around between atoms, they’re not easily removed from the metal as a whole

39. Properties of Metals
Metals are good conductors of electricity b/c of delocalized electrons move around.

40. Properties of Metals
The more delocalized electrons that are free to move the harder/stronger the metallic bonds are.
Alkali metals considered soft and not as strong b/c they have only 1 delocalized e-
Transition metals like chromium, iron, and nickel have more delocalized e- and are harder and stronger

41. Metal Alloys Due to the nature of metallic bonds
Easy to introduce other elements into a metallic crystal to make an ALLOY.
Alloy – is a mixture of different elements that has metallic properties.
Properties depend on which elements they contain.
2 types
Substitutional – take out some of the atoms and fill with similar sized atoms
Ex: sterling silver, brass, pewter, 10 carat gold
Interstitial – small holes filled with smaller atoms (strengthens)
Ex: carbon steel

42. Stainless steel (instruments, sinks, appliances)

43. Pewter (tableware)

44. Gold -10 carat (jewelry)

45. Dental amalgam (dental filings)

46. Cast iron (casting, cooking pans)

47. Bronze (bearings, bells, medals)

48. Brass (plumbing, hardware, lighting)

49. Alnico (magnets)

50. Lead shot (shotgun shells)

51. Practice
Complete the 8.4 worksheet in your packet