1. METALS
Bonds and
Properties
Alloys
Pure Elements

2. Hmmm…. How much is this shiney Gold worth !? 400 ounces (27.5lbs)
Many metals have high luster
Hmmm….
How much is this
shiney Gold worth !?
400 ounces (27.5lbs)
$ / ounce
$473, per bar
12 bars =
$5,678,400.00

3. Metal bonding
Metals: form organized lattice structures similar to ionic cmpds
adjacent atoms in metal lattice are all same
close proximity of atoms allows outer electron energy levels to overlap
So…

4. Na 3s Na 3s1
overlapping valence electron orbitals

5. electrons in outer valence shell can move freely through these overlapping energy levels:
results in “sea of mobile electrons”
allows (+) metal cation to form

7. sea of electrons: binds each metal cation to neighboring cation
this creates the metal bond:
due to electrostatic attraction between (+) metal cations & sea (-) electrons

8. Metal Properties How do electrons do this?
sea of mobile electrons gives metals their unique properties
since e- move freely from place to place metals can:
conduct electricity (flow of electrons)
conduct heat
account for being:
malleable
ductile
shiney (luster)
How do electrons do this?

9. most metals have high melting points
large amount of energy needed to overcome both IMF and strong bonding forces of metals in order to change phase

10. - + Electrical Conductivity e- flow through metal:
Flow of electrons
e- flow through metal:
e- travel through wire from battery, through metal and return to (+) terminal of battery
free flowing e- will travel through metal due to attraction of (+) metal cations

11. If apply force to structure of metals:
metal atoms shift away from force & free electrons bond newly overlapping metal cations together
metal’s shape is deformed but shift doesn't separate metal atoms
If apply force to structure of ionic compounds:
forces like charges to align (+) to (+) & (-) to (-) resulting in shattering due to repulsion forces
Metal
Non-Metal

12. as # of electrons that can be delocalized ↑ so does:
Hardness and Strength
Na has one valence electron that can be delocalized so:
- is relatively soft ( can be cut with a butter knife)
Mg has two valence electrons that can be delocalized so:
- still can be cut but is much harder than Na
transition metals have varied # of e-'s that can be delocalized
- chromium (Cr+6) is very hard and has high strength

13. Alloys mixture of elements with metallic properties
mixture can be adjusted to get desired properties
two types:
substitutional and interstitial alloy
(depends on size of elements – same or different size)

14. Common alloys brass: Cu & Zn bronze: Cu, Sn & Al pewter: Sn, Pb & Cu
solder: Pb & Sn
rose gold: Cu & Al
white gold: Au & Ni, Pd or Pt
sterling silver: Ag & Cu
steel: C & Fe
stainless steel: Cr & Ni