Chalkboard with description of periodic table notation for argon.  There is a square with three values in it.  Top has atomic number, center has element symbol, and bottom has atomic mass value.  The atomic number equals number of protons and also the number of electrons in a neutral atom.  Atomic mass equals the mass of the entire atom.

Check out the blackboard. That box on the left has all of the information you need to know about one element. It tells you the mass of one atom, how many pieces are inside, and where it should be placed on the periodic table.

In the next section we're going to cover electron orbitals or electron shells. This may be a new topic to some of you.

Electrons In The Shells

Take a look at the picture below. Each of those colored balls is an electron. In an atom, the electrons spin around the center, also called the nucleus. The electrons like to be in separate shells/orbitals. Shell number one can only hold 2 electrons, shell two can hold 8, and for the first eighteen elements shell three can hold a maximum of eight electrons. As you learn about elements with more than eighteen electrons you will find that shell three can hold more than eight. Once one shell is full, the next electron that is added has to move to the next shell.

So... for the element of ARGON, you already know that the atomic number tells you the number of electrons. That means there are 18 electrons in an argon atom. Looking at the picture, you can see there are two electrons in shell one, eight in shell two, and eight in shell three.


Argon Orbital GraphicArgon Electron List

► More about the history and places to find argon.
► Next element of the periodic table.



Link to Cosmos4Kids.com Link to Biology4Kids.com Link to Chem4Kids.com Link to Geography4Kids.com Link to Physics4Kids.com Link to NumberNut.com Rader Network Side Navigation


Examples of Compounds with Argon

Argon

Argon is the third of the noble gases or inert gases. It is very non-reactive. So much so, that it forms compounds with virtually no other elements. Just like neon (Ne) and helium (He), argon (Ar) usually floats around all by itself.

It is non-reactive because the shells are full. Argon has three electron shells. The third shell is filled with eight electrons. That is why it does not easily combine with other elements.

Ar
Line Break
Ar
Line Break
Ar



Related Links
- Chem4Kids: Periodic Table
- Chem4Kids: Atoms
- Chem4Kids: Compounds
- Chem4Kids: Helium
- Chem4Kids: Neon
- Chem4Kids: Noble Gases

RETURN TO TOP
or
Search for more information...

* The custom search only looks at Rader's sites.

Chem4Kids Sections

Rader's Network of Science and Math Sites