1. The Periodic Table An old story told in a new way
2. Lets start with a song So who can explain the periodic table
for me now?
3. Hmmm lets start at the very beginning What is the purpose of
the Periodic Table? To summarize and predict the chemical
properties of real elements
4. Now for a bit of history and fun facts Russian chemistry
professor Dmitri Mendeleev published the first periodic table in
1869 Carbon is unique in that it is known to form up to 10 million
different compounds. Francium is the rarest element on earth. Only
a few ounces of it on earth at any given time. The country
Argentina is named after the element silver (symbol Ag) which is
argentum in Latin. The only letter not in the periodic table is the
letter J. Each element has its own name and abbreviation Some of
them are easy to remember, like H for hydrogen. Some are a bit
harder like Fe for iron or Au for gold.
5. Actual picture of a Hydrogen Atom To understand the Periodic
Table, we need to understand What is an Element? An element is an
Atom such as Hydrogen or Helium An atom has a Shell = 1 Electron
for Hydrogen Just so you know . Electron has a negative charge
(flows though electric cables) Proton has a positive charge An Atom
is ALWAYS electrically neutral (no charge) Hydrogen Size = 53 x
10^-12 m An atom has a Nucleus = 1 Proton for Hydrogen Radius =
10^-15 m = Super Tiny! To compare A hair is about a Billion times
larger than Hydrogen atom
6. What is the Nucleus good for? The nucleus is the center of
an atom The nucleus has most of the mass of an atom, though it is
only a very small part of it The nucleus is made up of protons
(positive charge) and neutrons (no charge) Rows of the periodic
table are organized by increasing atomic number. And each row is
called a period The nucleus is held together by the nuclear force
The atomic number is equal to the number of protons in the
atom
7. Again The Rows or Periods of the periodic table count the
number of protons in an atom!
8. What is the Shell good for? The Shells of an atom hold the
electrons The number of electrons determine which group of the
periodic table an atom belongs to The number of electrons in the
outer shell (a shell that is not filled) determine the chemical
properties of an element If a shell is filled (for example 2
electrons in the K shell), the element does not react with other
elements. It is called stable! The less electrons in a shell, the
more chemically reactive an element is
9. Again The group of an element is determined by the number of
electrons in its outer shell Alkali Metals are the most reactive
elements! Why? What do they have in common?
10. Why is the periodic table periodic? Lets look at a Group
Hydrogen Lithium
11. Why is Hydrogen and Lithium in one Group? Hydrogen and
Lithium and all the other elements in the Alkali Metal Group have a
single electron in their outer shell
12. Now the TEST!!!!! Nobel Gases are the least reactive atoms
Why? What do they have in common?
13. Wait one more a trick question Why does the 1st period only
have Hydrogen and Helium?
14. Can you now predict what happens? Oxygen misses 2 electrons
to make its outer shell complete! It takes the electrons from
Hydrogen, as it has a stronger electric force (more electrons) than
Hydrogen! But it is not strong enough to kick the Hydrogen nucleus
away
