Chapter 7 Lesson 1Organization of the Periodic Table

How are the elements on the Periodic Table arranged?The elements are arranged on the periodic

table according to their atomic number.

Each element is on a square, and it contains key information. Highlight This!!

Remember?

Element Name

Atomic Number

Element Symbol

Mass Number

Periods and GroupsThe periodic table is also arranged into

horizontal rows called Periods.These are numbered 1 to 7

As you go across a period, the atomic number increases by 1. Highlight This!!

Periods and GroupsThere are also vertical columns on the

periodic table called Groups.These are numbered 1 to 18

Generally, groups of elements have similar chemical and physical properties.

What in the world are those elements at the bottom?The elements at the bottom of the periodic

table are called the Lanthanide and Actinide Series. These are known as the rare earth elements.

Highlight This!!

They are metals! Highlight This!!

They are on the bottom in order to save space.

This is too much empty space!!!

Facts about the rare earth elements

Lanthanides are used in products such as hybrid cars, permanent magnets, and more.

The actinide americium is used in smoke detectors.

Elements that have an atomic number greater than uranium (92) are often called "transuranium." Many of these elements are man-made under the conditions of nuclear reactors.

Both actinides and lanthanides are highly reactive with elements from the halogen group.

Facts about the rare earth elementsAll of the lanthanides have at least one stable isotope

except for promethium.

None of the actinides have a stable isotope. They are all radioactive.

In WWII, atomic bombs were charged with the actinide plutonium.

Plutonium was a power source for Voyager space crafts launched in 1977

Plutonium is also used in artificial heart pacemakers.

Facts about the rare earth elementsPlutonium was also used to generate the 1.21

gigawatts of electricity needed to power the DeLorean time machine.

https://www.youtube.com/watch?v=MVDosiqfJE0

MetalsThe metal blocks are colored blue in your

textbook. Properties of Metals:

Luster, which is shineMalleable, which means it can be hammered or

pressed without cracking.Ductile, which means they can be stretched or

pulled into wires.Conductive, which is the ability to transfer

electricity or heat.

Reactive MetalsThe most reactive metals are found in group 1

and 2. Highlight This!!

Reactive means it combines easily with other substances to form compounds.

The metals in group 1 and 2 are so reactive that they are never found in nature by themselves! They react with water and the oxygen in the

air.

NonmetalsNonmetal blocks are colored yellow in your

textbook.

Their properties are opposite of the properties of metals:Brittle, which means they break easily.They do not have luster.They cannot be easily shaped.They are not good conductors of heat and

electricity.

Reactive NonmetalsThe most reactive nonmetals are located in group

17 of the periodic table. Highlight This!! They are known as halogens Highlight This!!

They are also not found by themselves in nature.

Noble GasesThe noble gases are nonmetals, but they are unique. They make up group 18 of the periodic table. Highlight This!!

The noble gases are extremely stable, so they ARE often found by themselves in nature. If they are found in compounds, it is not a natural

compound.Because scientists have figured this out, we now know that

the noble gases are not unreactive.

Semimetals or MetalloidsSemimetals are colored green in your

textbook.

They have properties of both metals and nonmetals.

They are good semiconductors…which means they don’t conduct electricity as well as a metal, but they do conduct electricity better than a nonmetal.

Importance of SemiconductorsThe combination of different semiconductor

types together helps control electrical signals.

Semiconductors are used to manufacture electronic devices and integrated circuits. Like radios, TV's, computers, video games, and

medical diagnostic equipment.

Different types of periodic tablesEven though we use 1 periodic

table in this class, it is important to know that it is not the ONLY kind of periodic table.

Different types of scientists needs periodic tables with different information. For example: Chemists and

physicists need information about atomic structures and astronomers need information on how much of each element is found in the solar system.