Atomic Theory

This particle is found in the nucleus and has a positive charge

• Electron
• Proton
• Neutron

This is a negatively charged particle found outside the nucleus

• Electron
• Proton
• Neutron

This contains most of the mass of an atom

• Electron Cloud
• Nucleus
• Electron

What scientist is best known for his "Plum Pudding" model of the atom?

• J.J. Tomson
• Ernest Rutherford
• John Dalton
• Democritus

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

What does the nucleus of an atom contain?

• Electrons and neutrons
• Protons and neutrons
• Neutrinos and positrons
• DNA and RN

Which scientist proposed a model of the atom in which the electrons are orbiting at different levels?

• Niels Bohr
• James Chadwick
• John Dalton
• Ernest Rutherford

Which scientist saw the atom as a positively charged sphere with negative particles (electrons) embedded within?

• J.J. Thomson
• Niels Bohr
• John Dalton
• Ernest Rutherford

Bohr's model of the atom proposed that ___.

• electrons move around the nucleus in fixed orbits
• neutrons move around the nucleus
• neutrons do not exist, but are just paired protons and electrons
• the nucleus spins

Which scientist is responsible for first discovering that all the atoms of a particular element are identical but are different from the atoms of all other elements?

• Dalton
• Thomson
• Bohr
• Rutherford