families periodict.ppt (1)
TRANSCRIPT
Families :groups of elements that have similar
chemical properties.
five families
Alkali metals
Alkaline earth metals
Transition metals
Halogens
Noble gases
Alkali Metals
(Li, Na, K, Rb, Cs, Fr)
Most reactive family of metals
Group 1: only 1 valence electron
Never found free in nature
Kept in mineral oil or
inert gas in lab
Alkali Metals
(Li, Na, K, Rb, Cs, Fr)
Very reactive with nonmetals, especially Halogens like chlorine
Very reactive with oxygen (form oxides)
Very reactive with water (hydroxides)
Alkali Metals
(Li, Na, K, Rb, Cs, Fr)
Metals (but not always ‘typical’ metals*)
Good conductors of heat/electricity
Malleable and ductile
Solid at room temperature
M.P. and B. P. lower than most metals*
All soft (can be cut with a knife) and shiny silver and lighter (less dense) than other metals (Li, Na and K float on water)*
Alkaline Earth Metals
(Be, Mg, Ca, Sr, Ba, Ra)
2nd most reactive family of metals
Group 2: only 2 valence electrons
Never found free in nature
Alkaline Earth Metals
(Be, Mg, Ca, Sr, Ba, Ra)
Metals
Similar properties to alkali metals
Electrical conductors
Malleable and ductile
Shiny Silvery white solids
But harder and more
dense with higher M.P.
and B.P. than group 1
Transition Metals
21 (Scandium) through 29 (Copper)
39 (Yttrium) through 47 (Silver)
57 (Lanthanum) through 79 (Gold)
89 (Actinium)
and all higher numbers
Transition Metals
Have special electron rules
Can use two outermost shells to bond with other
elements
Can bond with many elements in a variety of shapes
Transition Metals
Properties vary but most …
have lower reactivityDon’t react quickly with H2O or O2
form brightly colored compounds
Transition Metals
Properties vary but most are…Very good conductors of heat/electricity
Malleable and ductile
Hard, tough and strong
Lustrous and shiny
High M.P.
High density
have lower reactivity
The Halogen Family
(F, Cl, Br, I, At)
Most reactive family of nonmetalsGroup 7: 7 valence electronsNever found free in nature
The Halogen Family
(F, Cl, Br, I, At)
Nonmetals
Poor conductors of heat & electricityCrumbly and brittle (when solid)M.P. and B. P. are lowCharacteristic colors and odorsToxic or poisonous
The Noble Gases
(He, Ne, Ar, Kr, Xe, Rn)
Unreactive (stable) family of gasesGroup 8: all have full outer shells
2 valence electrons for Helium
8 valence electrons for all othersAlways found free in nature
Do not form compounds◻Some Xe compounds have been formed,
but they are not very stable
The Noble Gases
(He, Ne, Ar, Kr, Xe, Rn)
Nonmetals
Colorless, odorless, tasteless gases at R.T. (Earth’s atmosphere)nonflammableVery low B.P. and M.P.
Hydrogen
Hydrogen
properties of both group 1 and 7typically shown listed with group 1
non-metallightest element
Least dense element
diatomic gas (RT)
colorless, odorless, and
tasteless
highly flammable
Atomic Mass
Weight by dozens
1 doughnut = 30g
12 x 30g = 360g = mass 1 dozen doughnuts
1 egg = 60g
12 X 60g = 720g = mass 1 dozen eggs
1 person = 60000g
12 X 6000g = 720000g = mass 1 dozen people
Atomic Mass
Weight by dozens
One dozen atoms??
Can you place 1 dozen atoms (12) in a container
and weigh them?
Can you place 602,214,150,000,000,000,000,000
atoms in a container and weigh them?
http://science.howstuffworks.com/avogadros-number.htm
Atomic Mass
Weight by Avogrado’s number: 6.022 x 1023
6.022 x 1023 atoms of H = 1.008g
6.022 x 1023 atoms of Au = 197g
6.022 x 1023 atoms of O = 16g