THE PERIObIc TABLE
•
A classification system that places elements with
properties
near each other on a chart
•
bimitri
(1869)
•
Each block represents a different
•
Elements are made up of
that will retain the identity of the element
•
Atoms have equal numbers of
•
Atomic Number
o
was one of the first scientists to design such a table
!‘- /
the number of
-
an c.
Z3
is the smallest unit
and electrons so they are
that an atom of a particular element has
Ex: Sod iumas atomic number is LL - each Na atom will always have 11 protons
•
Each element has a ,w
•
Early periodic tables were arranged in order of increasing atomic sS
periodic tables are ordered by increasing atomic
2
v
atomic number
modern
Alkali Metals (H, Li, Na, K, ftb, Cs, and Fr)
form
I ions (recall Tooth & Notch)
1 C , compounds (chlorides) such as HCI and LiCI, and NaCl
form E
Form 1E C)
compounds (oxides) such as H
0 E element
2
c Ce—
Extremely
- they form compounds readily
Shiny, gray-white metals
Loe-c
density & melting point than other metals
-
-
-
-
Alkaline Earth Metals
(Be, Mg, Ca, Sr. Ba, Ra)
Form C) ions (lose 2 electrons)
chlorides Ex. MgCl
Form
2
Form C) C) oxides, such as MgQ
Le-ss
ethan alkali metals, but more reactive than most metals
Together with alkali metals, known as
-
-
Transition Metals
(able to hammer into thin sheets)
(able to be drawn into wires)
Aboufj% of elements
Harder, less reactive, higher melting point
in compounds
C o’oc S
Some intense
/
-
-
-
-
-
Halogens (Fcijr
, At)
I
2
Form I ions (gain 1 electron)
u e_
form compounds readily
S
greenish-yellow
2
which are TOXIC!!
, Cl
2
F
cS
at room temperature
2 isa
Br
What medicinal use does this have?
12 is a gray-purple c1
-
-
-
-
-
.
-
(He, Ne, Ar, Kr, Xe, Rn)
‘
Almost entirely nonreactive (‘1 iJE
)
at room temperature
Which would you find in Las Vegas?
)‘Js.
Which would you find in your basement? And why worry about it? \C
avoid?
Noble Gases
-
-
-
-
‘
i\
.