Download The Periodic Table

Grouping the Elements
A sample square
Grouping the Elements
• The elements in a family or group in the periodic
table often, but not always, share similar
properties.
• The properties are the same because the
elements have the same number of electrons in
their outer energy level.
Reactive elements
• Atoms in these elements take, give, or share
electrons with other atoms in order to fill the outer
valence shell. They do this to form a compound
with another element.
Hydrogen
•
•
•
•
•
•
•
•
•
•
Electrons in outer level: 1
Don’t match the properties of any groups
Hydrogen belongs to a family of its own.
Most abundant element in the universe
Hydrogen is a diatomic, reactive gas.
Hydrogen reacts violently with oxygen. The hot water vapor that
forms as a result pushed the space shuttle into orbit.
Placed above the group 1 elements because it has only 1 electron
in it’s valance shell and can give one away
Properties are more like atoms of alkali metals
Hydrogen was involved in the explosion of the Hindenberg.
Hydrogen is promising as an alternative fuel source for cars
Group 1: Alkali Metals
• Electrons in outer level: 1
• 1st column on the periodic table (Group 1) not including
hydrogen.
• Most often found in compounds
• Soft, silver-colored, shiny, low density
• are soft enough to be cut with a knife
• the densities of some elements are less than water
• Most reactive of the metals
• easily give away the single electron from the valence shell
• React violently with water (Stored in oil to prevent reacting
with water and oxygen in the atmosphere)
Group 2:
Alkaline-earth Metals
• Electrons in outer level: 2
• Second column on the periodic table. (Group 2)
• Still reactive but not as reactive as Group 1
because they have 2 electrons to give away in
the valence shell
• Typically found in compounds such as calcium in
chalk, plaster, cement, and of course, humans!
Groups 3-12:
Transition Metals
• Properties vary widely
• The atoms of the transition metals do not give away their
electrons as easily as in Groups 1 and 2 so they are less
reactive.
• Properties: shiny, good conductors of thermal energy and
electric current, higher densities and melting points
Transition
Metals
(yellow)
Lanthanides and Actinides
• These bottom two rows from Periods 6 and 7on the periodic
table are placed at the bottom to keep the table from being too
wide
Lanthanides
Actinides
Lanthanides
• Named lanthanides because they follow the element
lanthanum
• Shiny, reactive metals
• Some are used to make different types of steel
Lanthanides
Actinides
• Actinides follow the element actinium
• All are radioactive, which means they are unstable
• Atoms from a radioactive element can change into
atoms of a different element
• Elements after plutonium (94) do not occur in nature
Actinides
Group 13: Boron Group
•
•
•
•
•
•
•
Electrons in outer level: 3
Group contains 1 metalloid and 4 metals
Reactive
Solid at room temperature
Most common element is Al (aluminum)
Al is most abundant metal in Earth’s crust
1880’s Al more valuable than gold
Group 14: Carbon Group
•
•
•
•
•
•
Electrons in outer level: 4
Group contains 1 nonmetal, 2 metalloids, and 2 metals
Reactivity varies among the elements
Solid at room temp
2 metalloids in this group make computer chips
Diamonds and soot are both natural forms of carbon!
Group 15: Nitrogen Group
•
•
•
•
Electrons in outer level: 5
Group contains 2 nonmetals, 2 metalloids, and 1 metal
Reactivity varies among the elements
All but nitrogen are solid at room temperature; nitrogen
is a gas at room temp
• Nitrogen non reactive, phosphorous extremely reactive
and only found combined with other elements in nature
Group 16: Oxygen Group
• Electrons in outer level: 6
• Group contains 3 nonmetals, 1 metalloid, and 1
metal.
• All but oxygen are solid at room temperature
• Many things that stink, contain sulfur (rotten
eggs, garlic, skunks,etc.)
• Reactive
Groups 17 and 18:
Nonmetals Only
• Group 17: Most reactive nonmetals
• Group 18: Least reactive nonmetals; normally
won’t react with other elements
Group 17: Halogens
• Electrons in outer level: 7
• Contains only nonmetals
• Very reactive because they need to gain only 1
electron to complete valance
• Poor conductors of electric current
• React violently with alkali metals to form salts
• Never found uncombined in nature and combine
readily with other atoms, esp metals
• Physical properties of atoms in this group are
different
Group 18: Noble Gases
18
•
•
•
•
•
•
Electrons in outer level: 8 (2 for helium)
Contains nonmetals only
Unreactive under normal conditions
Colorless, odorless gases at room temp
All are found in Earth’s atmosphere in small amounts
Argon is the most abundant noble gas