Properties of the Elements
The Periodic Table continued…
The Elements of the Periodic Table
• Elements (matter composed of only ONE KIND
OF ATOM) can be divided into THREE CLASSES
based on their properties:
–METAL
–NON-METALS
–METALLOIDS (Semi-Metals)
METALS
• Metals are a class of elements having these
properties:
• Luster (shiny surface)
• Ductile (can be stretched into a thin wire)
• Malleable ( can be hammered into thin sheets)
• Good Conductors ( allow heat and electricity to
flow through them)
• Generally have 1 to 4 VALENCE ELECTRONS
-(most have 1 or 2)
Reactivity of Metals
• Metals will react with other elements (usually
non-metals) to form compounds.
– The metals in Groups 1 and 2 are very reactive.
– Group 1 and 2 metals are never found in their
PURE FORM in nature…they are in compounds
with other elements.
• Pure Metals must be obtained by chemically separating
compounds.
Group 1 ALKALI METALS
• The Group 1 Alkali Metals are very reactive with
water:
– Usually stored under kerosene or other oils to prevent
contact with water.
• ALKALI METALS VIDEO
• Some common uses:
• Lithium – batteries and medications
• Sodium – in salts of many kinds and water
regualtion in living things.
• Potassium – in salts, also important for muscle
function including the heart.
Group 2 Alkaline Earth Metals
• The Alkaline Earth Metals are also very reactive,
though not as much so as Group 1.
– Not found in PURE FORM in nature.
– Pure Metal is obtained by chemically separating
compounds.
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Some common uses:
Calcium – bones and salts
Magnesium – salts and metabolism
Barium – X-rays of the digestive system
Radium – Radioactive – used in cancer treatment
Groups 3-12 Transition Metals
• The Transition Metals Group consists of 38
elements.
• As with all metals, they ductile, malleable, and
are conductors.
• Many of these elements form very brightly
colored compound with other elements and are
used as paint pigments.
• Three noteworthy elements are iron, cobalt, and
nickel, these are the only elements known to
produce a magnetic field.
Some transition elements and their
compounds used as pigments:
Group 13 The Boron Family
• The Boron Family consists of 5 elements.
• Boron is considered a METALLOID while the
rest are considered metals, though they are
POOR CONDUCTORS.
• Some important elements in the group:
• Boron – used in detergents.
• Aluminum – many uses.
• Gallium – a silvery metal that will “melt in
your hand!”
Group 14 The Carbon Family
• The Carbon group consists of 5 elements.
• The group contains METALS, METALLOIDS and NONMETALS!
• Some important members of the group:
• Carbon – basis of life on earth (organic chemistry)
• Silicon/Germanium– used to make computer chips.
• Tin/Lead – metals known and used for centuries!
– Lead can cause serious damage to the nervous system.
Group 15 The Nitrogen Group
• This group is made up of 5 elements.
• This group also contains a NON-METAL,
METALLOIDS and one METAL.
• Some characteristics of the group:
• Nitrogen – makes up about 78% of the air.
• Phosphorus – used to make many products
from matches, to soaps to plastics.
• Arsenic – used to make poison!
• Bismuth – used to make Pepto-Bismol!
Group 16 The Oxygen Family
• The group consists of 5 elements.
• Contains NON-METALS, METALLOIDS and a
METAL.
• Some important elements:
• Oxygen – needed for living things to carry on
respiration (release of energy from glucose).
• Sulfur – an important element in proteins.
• Polonium – a rare radioactive metal.
Group 17 The Halogen Family
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The group contains 5 NON-METALS.
The name halogen means “salt-forming”.
All THREE STATES OF MATTER are found in the family:
Fluorine and Chlorine – gases
• Fluorine – healthy teeth and refrigerants
• Chlorine – disinfectant and table salt (sodium chloride)
• Bromine – one of only 2 liquid elements (what is the other
one??) - used as an industrial solvent.
• Iodine - a solid element essential for proper THYROID
function.
Group 18 The Noble Gas Family
• Contain 6 ODORLESS, COLORLESS gases that DO
NOT REACT easily with other elements.
• Common members of the family:
• Helium – a carrier gas.
• Neon – lights and medical lasers.
• Radon – odorless, colorless, RADIOACTIVE gas.
– 2nd leading cause of LUNG CANCER.