General ---------Biology ------------------Online--------------------------wilcox@sunline.net Ch.  2 :  The Chemical Context of Life

Subatomic Particles

proton (positively charged)
neutron (no charge/neutral)
electron (negatively charged)

Protons and neutrons act like particles and both "weigh" the same, i.e. 1 dalton.  
A proton in a gold atom is the same as a proton in a oxygen atom;  a proton is a proton is a proton; they are all the same.  Ditto for neutrons and electrons.

Electrons weight almost nothing, move at high rates of speed and act like a particle some times, and at other times electrons act like pure energy (as in light, radiation or a laser).  Protons (+) and electrons (-) attract each other ("opposites attract and like charges repel").  Your refrigerator magnet makes use of this principal.   Neutrons are "neutral" and not attracted by + or - charges.

This is important because the attraction of protons for electrons is what binds atoms 
together when they "react" to form molecules.

Summary:

• a proton is a proton is a proton, ditto for neutrons and electrons
• a proton weighs 1 dalton
• a proton has a + charge
• a neutron weighs 1 dalton
• a neutron has no charge (neutral)
• an electron weighs very little
• an electron has a - charge
• electrons act like pure energy (weightless with no mass) and like a very light weight particle 
• atoms are held together in a molecule by the attraction of one atom's proton (+) for another atom's electron (-)