Consider the Following… (in your notes)
How do you organize your life and the world around
you? What are the benefits to having a system of
organization?
Periodic Table
of the Elements
Chemistry MYP
Ms. Khan
In case you were wondering…
I actually don’t, but my
dear friend Chemistry
Cat does on my behalf!

(Yes, I said friend.)
Development of the Periodic
Table
Development of the Periodic Table
▪ organized arrangement of
the elements
▪ first list published in 1789
by Antoine Lavoisier
– 33 chemical elements
– grouped
as
gases,
metals, nonmetals, and
earths
Development of the Periodic Table
▪ Dmitri Mendeleev’s periodic
table first published in
1869
– more than 60 elements
– periodic table “rotated” in
comparison
to
modern
periodic table
– elements
ordered
by
increasing atomic weight
– new columns began when
characteristics of elements
begin repeating
Development of the Periodic Table
▪ modern periodic
developed in 1945
▪ 118 elements (94
naturally occurring)
table
are
▪ arranged by atomic mass
across rows
▪ arranged by physical and
chemical properties down
columns
▪ horizontal rows: periods
– numbered 1 – 7
▪ vertical columns: groups (or
families)
– numbered 1 – 18
– can be split into A and B
blocks
▪ A block: IA – VIIIA
or 1A – 8A
▪ B block
Modern Periodic Tables
Types of Elements
Metals
▪ metal: an element that is a good
conductor of heat and electricity
▪ located on the left “side” of the periodic
table
▪ most are solid at room temperature
▪ most have silver or gray-white luster
▪ malleable: can be hammered or rolled
into thin sheets
▪ ductile: can be drawn into a thin wire
Alkali Metals
▪ group 1 or 1A elements
▪ silver in appearance
▪ soft enough to cut with a knife
▪ most reactive metals
▪ react vigorously with nonmetals
▪ not found in nature as free elements
▪ react strongly with water, moisture
in air (stored in oil)
Alkaline Earth Metals
▪ group 2 or 2A elements
▪ harder, denser, stronger than alkali
metals
▪ silver colored
▪ react with water
▪ reactive metals
▪ not found in nature as free elements
Transition Metals
▪ group 3 – group 12 elements
– B block elements
▪ good conductors
▪ high luster
▪ less reactive than alkali & alkaline earth
metals
▪ palladium, platinum, and gold are
among the least reactive of all elements
▪ mercury exists as a liquid at room
temperature
Rare Earth Metals
▪ lanthanide series
– period 6 below table
– most are found in the Earth’s crust
▪ actinide series
– period 7 below table
– thorium, uranium, and plutonium
can be found naturally
– all are radioactive
▪ these
elements
sometimes
categorized as transition metals
Other Metals
▪ from group 13 or 3A elements
– aluminum, gallium, indium, thallium
▪ from group 14 or 4A elements
– tin, lead
▪ from group 15 or 5A elements
– bismuth
▪ from group 16 or 6A elements
– polonium
Nonmetals
▪ nonmetal: an element that is a poor
conductor of heat and electricity
▪ located on right “side” of the periodic
table
▪ either solid or gas at room temperature
– with the exception of bromine (liquid
at room temperature)
▪ brittle
▪ no common color
Halogens
▪ group 17 or 7A elements
▪ most reactive nonmetals
▪ react vigorously with metals
▪ gases: fluorine, chlorine
▪ solids: iodine, astatine
▪ liquid: bromine
▪ chlorine, bromine, iodine: used as disinfectants
▪ toxic
Noble Gases
▪ group 18 or 8A elements
▪ gases at room temperature
▪ odorless and colorless
▪ generally unreactive
▪ neon,
argon,
krypton,
xenon: used in lighting
▪ helium: used in balloons
Metalloids
▪ metalloid: an element that has some characteristics of
metals and some characteristics of nonmetals
▪ found between the metals and nonmetals (“stair step”)
▪ solid at room temperature
▪ less malleable than metals, not as brittle as nonmetals
▪ semiconductors (used in electronics)
▪ boron, silicon, germanium, arsenic, antimony, tellurium