Meet the Main Group Elements

1
Meet the Main Group Elements!

• Or Who are the Elements in Your Neighborhood?
• http//members.tripod.com/Tiny_Dancer/peopleinyour
  neighborhood.mp3

2
What Are All The Groups?
3
Groups Can Be a Family Affair

• There are also other, less specific, groups of
  elements. These groups are all over the table.
• Scientists group these families of elements by
  their chemical properties. Each family reacts a
  different way with the outside world.
• Sometimes families align with the columns or
  groups, sometimes they dont. Only tests will
  tell for sure!

4
Alkali Metals

• One electron in their outer (valence) electronic
  shell
• Tend to lose a single electron to form a 1
  charged positive ions
• Highly reactive!
• Combine with negatively charged ions to form
  salts
• Soft and easily cut
• Low densities melt at low temperatures.

Because they are so reactive,alkali metals are
alwaysfound in compounds.
5
Alkaline Earth Metals

• Two electrons in outer shell
• Tend to lose two electrons to form 2 positive
  ions
• Also very reactive
• Sometimes they bond with two halogen atoms (BeF2)
  and sometimes they form one double bond (CaO)
• Called alkaline because they are likely to form
  solutions with a pH greater than 7 (bases).

Alkaline earth metals are a major part of seas
shells andmagnesium (mag) wheels.
6
Boron Group

• Three electrons in outer shell
• Tend to lose three electrons to form 3 positive
  ions
• Boron is a metalloid. Others in group are metals.
• Boron and Aluminum have widespread commercial
  applications

Aluminum is used to makebaseball bats. Your body
heatwill melt Gallium.
7
Carbon Group

• Four electrons in outer (valence) shell
• Tend to share these four electrons to form
  covalent compounds
• Carbon can form an unlimited number of compounds.
• Most compounds in living things contain carbon.

Carbon makes up graphite,an excellent lubricant.
Siliconis a major part of many minerals.
8
Nitrogen Group

• Five electrons in their outer (valence) shell
• Tend to gain three electrons to form 3- charged
  negative ions
• 80 of our air is Nitrogen (living things need
  Nitrogen to make proteins).

Phosphorus is used to makematches. Liquid
Nitrogen willinstantly freeze a rose.
9
Oxygen Group

• Six electrons in outer (valence) shell
• Tend to gain two electrons to form 2- negative
  ions
• Oxygen is the most important and most abundant
  element on Earth!
• Plants produce oxygen during photosynthesis

Astronauts rely on oxygentanks to breathe.
Sulfur is ayellowish non-metal solid.
10
Halogens

• Chemically reactive!
• Not all halogens react with the same intensity.
  Fluorine is the most reactive and combines all of
  the time. As you move down the column, reactivity
  decreases.
• When a halogen combines with another element, the
  resulting compound is called a halide.

Salt and plastics bothcontain halogen
compoundsor halides.
11
Noble Gases

• Eight electrons in their outer (valence) shell
• They are chemically inert and do not combine with
  other elements
• They do not lose, gain, or share electrons
• All Noble Gases exist in the earths atmosphere

Helium makes blimps floatand other gases create
thecolors in Neon lights.
12
Transition Metals

• Numbers of electrons lost or gained varies
• Much less reactive than alkali and alkaline earth
  metals
• Often found in ores (minerals)
• Good conductors of heat and electricity

Transition metals make up most metal objects.
Some form colorfulcompounds.
13
Rare-Earth Metals

• Also called Lanthanides
• Except for Promethium, all Lanthanides occur in
  nature
• Pure Lanthanides look like steel and have
  steel-like properties
• Tiny amounts of pure Lanthanides are used in
  Lasers

Rare earth metals have properties that make them
useful in certain special devices.
14
Actinides

• Most are synthetic and are made in laboratories.
  Only Actinium, Thorium, Protactinium Uranium
  occur naturally
• All isotopes of all the actinides are radioactive
• Actinide metals tarnish readily in air
• React with boiling water or dilute acid to
  release hydrogen gas

All isotopes of actinides are radioactive. Most
are synthetic.
Learn more http//www.ucc.ie/ucc/depts/chem/dolch
em/html/elem/group.html
15
Class Project We are going to create a Periodic
Table of you!

• Step One Complete the survey to help identify
  your main characteristics
• Step Two Group like students into families
• Step Three Create a giant PT with each student!

http//www.chemsoc.org/viselements/pages/pertable_
fla.htm