Discovery of electrons and the nucleus

What were John Dalton three contributions to atomic history?

• Created the atomic theory

• Discovered that the atom is mostly empty space

• Believed that atoms of a given element are identical

• Hypothesized that the atom is a tiny, hard sphere

• Believed that the universe was made of tiny "uncuttable" particles

Tags

NGSS.MS-PS1-1

What were J. J. Thomson's three contributions to the atomic theory?

• Discovered the electron

• Discovered the nucleus -did the gold foil experiment

• Used the cathode ray tube in his discovery

• Created a model of the atom with electrons moving around the nucleus in fixed orbits

• Created the "plum pudding" model of the atom

Tags

NGSS.MS-PS1-1

Which model of the atom proposed that atoms were positive spheres with negative electrons in them?

• Heliocentric Model
• Solid Sphere Model
• Plum Pudding Model
• Planetary Model

Tags

NGSS.MS-PS1-1

Which scientist saw the atom as a solid sphere?

• Dalton
• Thomson
• Rutherford
• Bohr

Tags

NGSS.MS-PS1-1

Who's model is this?

• Thomson
• Rutherford
• Democritus
• Bohr

Tags

NGSS.MS-PS1-1

Who came up with this model?

• Dalton
• Thomson
• Rutherford
• Bohr

Tags

NGSS.MS-PS1-1

In Dalton's Atomic Theory, all elements consist of __________ that cannot be divided.

• Atoms
• Parts
• Molecules
• Hydrogen

Tags

NGSS.MS-PS1-1

In the Thomson Model, he discovered the existence of what particle?

• Electrons
• Protons
• Neutrons
• Quarks

Rutherford’s experiment determined that the nucleus of an atom is tiny, dense and  ______ charged. 

• neutrally
• negatively
• positively

Tags

NGSS.HS-PS1-8

The cathode ray experiments led to which particle being discovered?

• Nucleus

• Proton

• Neutron

• Electron