Transcript Atomic Number

Hi. I’m an atom of Lithium.
I’m so pleased that you’re going to
join me on a tour of my house.
* How can you tell that this is a lithium atom?
Everyone else calls it the
Periodic Table…
What do you notice about the ATOMIC NUMBER as
you read the chart left to right and down?
The atomic number increases!
What do you notice about the ATOMIC MASS as
you read the chart left to right and down?
The atomic mass increases!
(there are a few exceptions)
Review this…What do you notice about the
atomic number as you read the chart left to right
and down?
The atomic number increases - this is a
distinct trend by which the entire table
is organized...
What do you notice about the atomic masses as you
read the chart left to right and down?
The atomic masses get larger, although
there are a few exceptions!
Atomic Mass
This number indicates the total number of protons and
neutrons in the nucleus of a neutral atom.
Hydrogen is
• When you subtract the atomic number from
weird. It can
the mass, you are left with the number
have 0, 1 or 2
of neutrons. Round off the mass to
neutrons!
the nearest whole number first!)
BACK
Wow… say that again!
From this one table, you can
figure out what’s in the nucleus of
a neutral atom of each element.
The farther right and down you
go, the more protons there are,
and the heavier the atoms are!!
The Periodic Table of Elements
Atomic Number: this number indicates the number of
protons and electrons in a neutral atom. It is very significant, as
the number of protons is the primary identifier for any element.
hydrogen
helium
The periodic table is divided into 3 basic kinds of
elements:
1. Metals
2. Nonmetals
3. Noble gases
*The Noble Gases (Group VIII A) are not reactive. Please
note that the vertical columns are groups (families) of
similar elements exhibiting common characteristics. The
horizontal rows are called periods, and are related to the
number of energy levels in the elements.
Metals:
1. Metals have high melting and boiling points. They remain
solids under extreme heat.
2. They are good conductors of heat and electricity.
3. Most react with air to eventually “rust”.
4. They have a high density and metallic lustre.
5. They are malleable and ductile.
Let’s take a look!!
As you go along, write the names into
your own periodic table!
Alkali Metals: Group I A
Alkali Metals: (Group I A)
lithium, francium, potassium, rubidium, sodium and cesium
1. Very dangerous; highly reactive with air and water
- stored under oil.
2. Soft enough to cut with a knife.
3. They have low melting points and low boiling
points compared to other metals.
4. Low densities.
Alkaline Earth Metals: Group II A
Alkaline-Earth Metals: (Group II A)
beryllium, magnesium, calcium, strontium, barium, radium
1. Silvery-white colour characteristic of group
2. They are not quite as reactive as the alkali metals,
but still reactive with water; all tarnish in air.
3. Light and soft relative to other metals.
Calcium is an alkaline-earth metal that is found in
deposits of limestone rock, bones, teeth and shells of sea
creatures.
TRANSITION METALS
Properties of Transition Metals:
Transition metals form the center block of the periodic table . They
are sometimes called the B Groups (“Bridge” to the A groups).
1. They are less reactive than the pure metals generally.
2. They exhibit higher melting and boiling points
3. Good conductors of heat and electricity
4. Some of the transition metals are magnetic (iron, cobalt and
nickel)
5. Very ductile and malleable - gold and silver can be drawn into
very thin long threads...
6. These groups of metals contain many elements that are
commonly used - Zn, Au, Ag, Sn, Hg, Cu, Ni, Cr, Pt….
Lanthanide and Actinide
Inner Transition Metals
Lanthanide and Actinides: Inner Transition
Metals
1. All actinides (also called actinoids) are radioactive, and
rare.
2. They are often difficult to distinguish in nature.
3. All members are very unstable.
*These elements do share some characteristics and trends
like the other elements in the table, but do tend to be more
radioactive on average. They are also placed below the table
to shorten the space required by the rest of the periods.
Non Metals
Nonmetals:
phosphorus, boron, sulfur, hydrogen, arsenic, selenium,
tellurium, carbon, silicon, nitrogen, oxygen, and the halogens.
Although the nonmetals form a relatively small part of the
periodic table, they are vital to life on earth. The nonmetals form
the key building blocks for all life forms, primarily with carbon.
* Nonmetals can be found as a solid, liquid or a gas.
* They are poor conductors, dull, and brittle.
* They have low melting and boiling points.
Can you think of an example that defies the above definition? :)
Metalloids:
Aluminum, germanium, arsenic, antimony, tellurium,
polonium, astatine
•Solid at room temp
•are generally poor conductors, dull, and brittle.
•have relatively low melting and boiling points
•Metalloids can sometimes exhibit behavior of both a
metal and a nonmetal...remember that metals have a
metallic lustre, are malleable and ductile, and great
conductors!
Halogens (Group VII A)
Halogens: (A.K.A. “HALIDES”)
fluorine, chlorine, bromine, iodine, astatine
1. They form group VII A (17) on the periodic table.
2. Most are poisonous and have a strong odour
3. They react with metals to form salts.
4. They will form covalent/molecular bonds with other nonmetals,
and ionic bonds with other metals.
5. The ability to react and gain one electron decreases
as you go down the column: astatine is not nearly as reactive
as fluorine.(Fluorine is the most reactive nonmetal
of all, and diagonally across is the most reactive metallic element:
francium…)
Noble Gases (Group VIII A)
Noble Gases:
helium, neon, argon, krypton, xenon, and radon
1. The noble gases form group VIII A (18) and are rare.
2. They have very low melting and boiling points.
3. They are extremely unreactive, existing as monatomic gases.
4. Most can only be obtained by the fractional distillation of air.
5. Noble gases form their own unique group, and are not
considered as nonmetals…
Go to www.webelements.com to find out
more!
Thanks for touring my home!
You should be able to complete
your sheet now!
Come back soon!