Could someone explain to me how the octet rule works?

Also what makes atoms bond? I know it deals with electrons but that all I know.

What is the difference between the atomic number and mass? How can I figure out the number of electrons, protons and neutrons using these figures?

I keep reading my text book and it makes little sense.

[This message has been edited by gombowlzombie (edited 07-01-2003).]

atomic mass = protons+neutrons

atomic number = protons

mostly the number of electrons = protons

each atom has a nucleus of protons and neutrons (+&n) orbited by electrons <->

the electrons are arranged in shell rings

the inner shell is closest to the nucleus and holds up to 2 electrons

all other shells hold up to 8 electrons

when a shell is full a new one is made

Argon has atomic no. 18 it has 18 electrons it has 3 shells around the nucleus 2 electrons on the inner 8 in the middle 8 in the outer shell

all shells are full it isnt very reactive

Potassium is atomic no 19 2 electrons on the inner 8 on the second shell 8 on the third shell and 1 electron on the outer shell the outer shell isnt full so potassium is very reactive

when the outer shell isnt full with 8 electrons the atom will try to fill up the shell when the time is right atoms without a full outer shell are the most reactive

when an atom is missing some electrons or has extra it becomes an ion missing electrons makes it positive charged to many makes it negative charged it will seek an atom with the opposite charge it may stick to an atom of another element each atom will trade the electron back and forth and form a compound this is ionic bonding

if 2 or more ions are missing electrons they might join and share the electrons each has instead of trading back and forth all will use the electrons making the outer shells full for all and forming a compound this is covalent bonding

The "shell" model is a very simplistic, model that works for the low mw elements. Don't rely on it to figure out everything and don't rely on it to explain bonding behavior or bond angles or anything other than as a methaod to remember the valence of simple atoms.

Bonding is caused by the sharing of electron pairs between nuclei in molecular orbitals. These orbitals are devived from incomplete atomic orbitals. The basic attraction of a bond is that it forms a favorable low energy state.