Elements and Their Properties
A. Metals
1. Properties
a. Hard and shiny (exception: mercury)
b. Good conductors of heat and electricity
c. Malleability - can be rolled or beaten into sheets
d. Ductility - can be drawn into wire
e. They have 3 or fewer outer electrons
f. They give up their outer electrons in chemical reactions
g. They usually form ionic bonds with nonmetals
2. The metallic bond
a. In a metal, positive ions are surrounded by a sea of electrons
b. Valence electrons are not held tightly to any particular nucleus
c. This explains malleability and ductility (electrons are in layers that
slide)
d. It also explains why metals are good conductors of electricity
3. Most of the elements are metals
4. Families of metals
a. Alkali metals
1) Group 1 (all have 1 valence electron)
2) Are the most reactive of all metals (only found in compounds in
nature)
3) Can explode when exposed to water
4) Examples
a) Sodium is in table salt
b) Potassium is necessary for plant growth
b. Alkaline earth metals
1) Group 2 (all have 2 valence electrons)
2) Are very reactive (only found in compounds in nature)
3) Examples
a) Beryllium is in beryl (gemstone is emerald)
b) Magnesium
1] Brightness - fireworks, flashbulbs
2] Strength & lightness - cars, planes, spacecraft, ladders, ballbats
3] Chlorophyll
c) Calcium is used by animals for bone strength
d) Barium is used to detect digestive disorders
c. Transition elements
1) Groups 3 - 12
2) Examples
a) Iron, cobalt, and nickel are the only elements that can create a magnetic field
b) Iron is the most widely used metal
c) Nickel gives strength to metal alloys and makes a protective, shiny coating
d) Very unreactive
e) Copper is used as electrical wiring
f) Silver is used in film and jewelry
g) Gold is used in jewelry and fine wiring components
h) Zinc is used to plate iron
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