2.4- Three types of chemical bonds are ionic, covalent, and hydrogen

covalent bond

A chemical *bond* that occurs when atoms *share electrons* -The strongest chemical bond

ionic bond

A chemical *bond* that occurs when atoms *transfer electrons*. -Generally produce salt crystals -produces medium strength level bond

Dipole

A molecule that has two poles (one end is positive, the other negative).

Nonpolar covalent

A type of *bond* that forms when electrons are *shared equally.*

hydrogen bond

Chemical *bond* that occurs as weak *attraction between dipoles*. -is the cause of water surface tension -weakest bond -more an attraction than a bond

valence shell

The *outermost* energy shell of an atom; contains the valence electrons involved in the chemical reactions of that atom.

octet rule (rule of eights)

The tendency of atoms to interact in such a way that they have eight electrons in their valence shell.

Polar covalent

a type of *bond* that forms when electrons are *not shared equally* - Generally produces dipoles (one end is positive, the other negative)

electron shells (energy levels)

these surround the nucleus of an atom; the electrons are located here.

Chemical bond

this is force that holds two atoms together.