3º E.S.O THE CHEMICAL BOND

Hello everyone,
As I told you, I am going to use this blog to attach some of the summaries and images that you don't have in your regular textbook. I really hope they are useful to study the chemical bond.

An atom is stable if the outermost shell has 8 electrons (we call it an octet)

Only the atoms in the 18th group has it, the rest must:

- SHARE electrons GIVE them away or TAKE them from other atoms.

When this happens, they form a BOND

A BOND IS THE FORCE OF ATTRACTION THAT KEEPS TWO OR MORE ATOMS 

TOGETHER

The outer shell of noble gases is completely fulfilled with electrons, so they are not likely to form any bond

IONIC BOND. It happens when two atoms interact:

-One of the atoms loses electrons

-The other gains electrons

That way, both reaches the configuration of a noble gas

It happens generally between a metal and a non-metal.

When the atoms combine to form an ionic bond, they usually make CRYSTALS.

In a crystal, every atom is in a specific position. It is an organised structure.

COVALENT BOND. It happens generally among NON METALS. 

Atoms share electrons to form a covalent bond.

When non metals bond, they form MOLECULES