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TRANSCRIPT
Introduction to the Periodic Table
November 4, 2014
Our Objectives
v Describe the arrangement of elements in the modern periodic table
v Understand the trends that established the modern periodic table
v Locate periods and groups in the period table
A Little Bit of the History..
v Mendeleev first organized the periodic table by atomic mass
v But, the modern day periodic table is organized by atomic number
Dmitri Mendeleev
A Little Bit of the History..
Mendeleev’s original Periodic Table
How are Elements Classified?
Three Regions
- Metals, Nonmetals, and Metalloids
Properties of Metals
v Metals are:
v Good conductors of heat and electricity
v Shiny
v Ductile (can be stretched into thin wires)
v Malleable (can be pounded into thin sheets)
v Mostly solid at room temp (except Hg)
Properties of Non-Metals
v Non-metals are:
v Poor conductors of heat and electricity
v Not ductile or malleable
v Brittle and break easily
v Dull
v Mostly gases Sulfur
Properties of Metalloids
v Metalloids (metal-like):
v Have properties of both metals and non-metals
v Are solids that can be shiny or dull
v Conduct better than non-metals but not as well as metals
v Are ductile and malleable
Silicon
OK, Let’s Review…
v What are some examples of metals? v Gold, silver, magnesium, lead, alumnium
v What is a metal that is liquid at room temp? v Mercury
v What are some examples of non-metals? v Oxygen, fluorine, nitrogen, sulfur
v What are some of the characteristics of the metalloids ?
v Better conductors than non-metals, are shiny or dull, etc.
The Periodic Table
v “A” groups are referred to an the representative elements because they possess a wide range of chemical and physical properties
v “B” groups are referred to as the transition metals v Notice their number is not in consecutive order from left
to right on as with the “A” groups
Periods: Horizontal Rows
Groups/Families: Vertical Columns
A 1, 2 A (3-8)
Let’s Look at the Families
• Alkali • Alkali Earth
• Halogen
• Noble Gases
Alkali Metals
v Elements in1st column (Group 1 or 1A)
v Not including hydrogen
v Very reactive metals, always combined with something else in nature (like in salt)
v Soft enough to cut with a butter knife
Li
Na
K
Rb
Cs
Fr
Alkaline Earth Metals
v Second column(Group 2 or 2A)
v Reactive metals that are always combined with nonmetals in nature
v Several of these elements are important mineral nutrients (such as Mg and Ca)
Be
Mg
Ca
Sr
Ba
Ra
Halogens
v Elements in group 17 or 7A
v Very reactive, volatile, diatomic nonmetals
v Always found combined with other elements in nature
v Used as disinfectants and to strengthen teeth.
F
Cl
Br
I
At
The Noble Gases
v Elements in group 18 or 8A
v VERY unreactive, monatomic gases
v Used in lighted “neon” signs
v Used in blimps to fix the Hindenberg problem
v Have a full valence shell
He
Ne
Ar
Kr
Xe
Rn
OTHER GROUP NAMES
• Group 3A or 13: BORON Family • Group 4A or 14: CARBON Family • Group 5A or 15: NITROGEN Family • Group 6A or 16: OXYGEN Family