negatively charged particles with a mass of 0.0006 a.m.u. (or just put zero)

their exact location around the nucleus is not known only know where they are most likely

to be found this is often called an electron cloud

or orbital many electron clouds or orbitals

can make up an electron level

for this class (Physical Science), each level or orbit, can only hold a certain amount of electrons 1st up to 2 electrons 2nd up to 8 electrons 3rd up to 8 electrons (really 18) 4th up to 8 electrons (really 32)

the properties of elements depends on how many electrons are in a particular atom’s different levels.

valence electrons are the electrons in the very last or outermost energy level

draw a chlorine atom

and a sodium atom

valence electrons are represented as dots around the chemical symbol for the element

Na

Cl

1. electromagnetic• opposite charges (+ and -) attract• same charges (+ and +) (- and -)

repel2. the strong force

• greatest of the four forces• “glues” the protons together

3. the weak force• important in radioactivity

4. gravity• weakest of the four forces• for subatomic particles, it is not

understood or may not even work at all

http://hyperphysics.phy-astr.gsu.edu/hbase/forces/funfor.html