J.J. THOMSON'S MODEL

Before Rutherford's discovery, people believed that J.J. Thomson's Plum Pudding Model was an accurate representation of all atoms.

By conducting a gold foil experiment, Rutherford knew Thomson was wrong because he believed there was a central positive charge in the atom.

Plum Pudding Model:

• Described an atom as being a positively charged body that contained free-floating, negatively charged electrons.

• Stated that the overall charge of an atom was neutral since the negative and positive charges canceled each other out.