2. What contribution did these scientists make to atomic models of the atom? a. Dalton-1st atomic structure
b. Thomson-electron
c. Rutherford-nucleus’s

A. Dalton - John Dalton created the very first atomic theory. Dalton viewed atoms as tiny, solid balls. His atomic theory had 4 statements:
1. Atoms are tiny, invisible particles.
2. Atoms of one element are all the same.
3. Atoms of different elements are different.
4. Compounds form by combining atoms.

B. Thomson - Thompson believed atoms were made mostly out of (+) charged material, like dough in a bun. The (-) charged electrons are found inside the (+) dough.

C. Rutherford - Rutherford discovered protons and the nucleus. He showed that atoms have (+) particles in
the center, and are mostly empty space. He called these (+) particles protons. He called the center of atoms the nucleus.