Transcript Chapter 6

Chapter 6
Developing The Periodic Table
Part 2
Families on the Periodic Table
• Columns in the periodic
table can be grouped into
families.
• Families may be one
column, or several
columns put together.
• Families have names
rather than numbers.
(Just like your family has
a common last name.)
Alkali Metals
• 1st column on the periodic
table (Group 1) not including
hydrogen.
• Most reactive family of metals,
always combined with
something else in nature (table
salt).
• Low density metals (Li, Na and
K are less dense than water).
• that are soft enough to cut
with a butter knife.
Alkaline Earth Metals
• Second column on the periodic
table. (Group 2)
• Second most reactive family of
metals, always combined with
nonmetals in nature.
• All of the alkaline earth metals
are found in compound form
within the earth's crust.
• Several of these elements are
important mineral nutrients
(such as Mg and Ca).
Calcium and Magnesium
Two Important Minerals
Magnesium & Calcium are
essential minerals for your health
• Calcium
Found primarily in dairy foods such as milk, cheese and yogurt.
Your bones eagerly absorb and store calcium necessary for
your body's growth and maintenance until you reach your mid
20's. After that, your body rapidly uses up the calcium to help
keep your bones strong. Failure to get enough calcium can lead
to osteoporosis (holes in the bones), brittle and easily
breakable bones, and tooth loss.
• Magnesium
Magnesium is one of the most important minerals your body
needs, and fortunately, it can be found in many of the foods we
eat, including many fruits, vegetables and dairy products.
Failure to get enough magnesium can lead to muscle soreness,
heart and blood pressure problems, as well as nervous
disorders.
Magnesium Keeps the Doctor at Bay
By W. Gifford-Jones, M.D.
Special to The Epoch Times
Apr 24, 2006
Recently, a healthy 18-year-old
basketball player and healthconscious jogger died suddenly.
The initial diagnosis was death
from coronary artery disease due
to high blood cholesterol. But the
cause of death eventually proved
to be magnesium deficiency.
Transition Metals
• Elements in groups 3-12
• Less reactive harder
metals
• Includes metals used in
jewelry and construction.
• Metals used “as metal.”
Less reactive but can still react
Iron (Fe)
Rust (Fe2O3)
Oxygen Family or Chalcogens
• Elements in group 16
• Oxygen is necessary
for respiration.
• Many things that stink,
contain sulfur (rotten
eggs, garlic,
skunks,etc.)
Halogens
• Elements in group 17
• Most reactive of the
nonmetals.
• Always found combined with
other elements in nature.
• Have a strong unpleasant
odor and are poisonous
(have been used as
chemical weapons).
• In low doses can be used as
disinfectants (chlorine in
drinking water and in pools).
The Noble Gases
•
•
•
•
Elements in group 18
All are gases.
VERY non-reactive.
Have a full outer
energy level.
The Octet Rule
• The octet rule states that an atom's outer
energy level is full and most stable when it
contains eight electrons.
• This stability is the reason that the noble
gases are so non-reactive.
Exception to the Octet Rule
The “Duet Rule”
• The first energy level can only hold two
electrons.
• Elements such as Hydrogen and Helium
that only have one energy level follow a
“duet rule”.
• The duet rule states that two electrons will
stabilize an atom with only one energy
level.
Rare Earth Elements
0
• The thirty rare earth
elements are
composed of the
lanthanide and
actinide series.
• The rare earth
elements are metals.
• Many of these
elements are
synthetic or manmade. (Primarily
elements after
plutonium)
Homework
• Chapter 6 – Worksheet 1