greeks= proposed atoms are made of earth

jj thomson= worked with cathode ray

chadwick= discovered the neutron

rutherford= discovered the nucleus

jj thomson= identified the electron

protons= positive charge, 1+ g (amu), inside the nucleus

neutrons= neutral charge, 0g (amu), inside the nucleus

electrons= negative charge, 1-g(amu), outside the nucleus

mass number= protons + neutrons

net force= protons + electrons

atoms= individusl building blocks of matter; pieces of elements from the table

molecules= anything made up of at least 2 non-metal atoms; can either be the same element

Protons and neutrons- the particles found in the nucleus

Protons- the particles that determine the identity of an element