Atomic Model

What contribution did John Dalton make to atomic theory? 

• He discovered that every atom was positively charged. 
• He discovered that every element consisted of one type of atom.  
• He discovered that atoms had nuclei. 
• He discovered that atoms could be divided into smaller parts. 

Place the following scientists in order, from earliest to latest: 
A) Ernest Rutherford
B) J.J. Thomson
C) John Dalton

• B,C,A
• C,A,B
• A,C,B
• C,B,A

Ernest Rutherford discovered that atoms were mostly _________________. 

• negatively charged
• positively charged
• electrons
• empty space. 

What are electrons?

• Negatively charged particles
• Neutrally charged particles
• Positively charged particles
• Uncharged particles

What does the nucleus of an atom contain?

• Electrons & Neutrons
• Protons & Neutrons
• Neutrinos & Positrons

J.J. Thomson used a cathode ray tube to find what particle in the atom?

• Proton
• Neutron
• Electron

What did Democritus, Dalton, Thomson, Rutherford, and Bohr all have in common?

• Identified new isotopes
• contributed to the development of the atomic theory
• conducted experiments where particles collided

According to Rutherford, what was in the center of an atom?

• an electron
• a nucleus
• a particle

Particle that cannot be cut

• atom
• electron shells
• neutron

subatomic particle that has a positive charge.

• electron
• neutron
• proton