Atomic Theory

In an atom, electrons move in definite orbits (rings) around the nucleus.

• Thomson
• Rutherford
• Bohr
• Democritus

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

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

Tags

NGSS.MS-PS1-1

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 that couldn't be divided. 
• He discovered that atoms had nuclei. 
• He discovered that atoms could be divided into smaller parts. 

Tags

NGSS.MS-PS1-1

Rutherford's gold foil experiment provided evidence that...

• negative and positive charges are spread evenly throughout the atom.
• alpha particles have a positive charge.
• gold is not a dense as previously thought.
• there is a dense positively charged nucleus at the center of an atom.

Tags

NGSS.MS-PS1-1

Who discovered the nucleus using the gold foil experiment?

• Democritus
• Robert Millikan
• James Chadwick
• Ernest Rutherford

He discovered the electron using cathode ray tube experiment.

• JJ Thomson

• John Dalton
• Ernest Rutherford
• Robert Millikan

His atomic model was depicted similar to a planetary/solar system

• Niels Bohr
• Joseph Thomson
• Ernest Rutherford
• Democritus

Tags

NGSS.MS-ESS1-2

What is the atomic number?

• the number of protons in the nucleus

• the number of neutrons in the nucleus

• the number of protons and neutrons in the nucleus

• the number of protons in the energy levels

Tags

NGSS.MS-PS1-1

What is the mass number?

• the number of protons in the nucleus

• the number of neutrons in the nucleus

• the number of protons and neutrons in the nucleus

• the number of protons and electrons in the atom

Tags

NGSS.HS-PS1-8

What is the atomic number of this atom?

• 1

• 3

• 4

• 7

Tags

NGSS.MS-PS1-1