Development of Atomic Models

Rutherford realized that the atomic nucleus was positively charged because

• it attracted alpha particles.

• it deflected alpha particles.

• it had no effect on alpha particles.

• it produced alpha particles.

Which of the following is the best evidence that the particles that make up a cathode ray had a negative charge?

• The particles were produced by many different metals.

• The ray was deflected toward a positive electric field.

• Line emission spectra for an element are always the same.

• The ray caused a phosphorescent screen to glow.

Tags

NGSS.HS-PS2-4

NGSS.HS-PS2-5

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.

JJ Thomson's experiment that he used to discover electrons

• gold foil experiment

• cathode ray experiment

• neither of these is correct

What is an alpha particle?

• It is a dominant particle in a subatomic world

• It is a particle that has 2+ charge

• It is a particle that has 2- charge

• It is a helium atom without a charge

What results did Rutherford observe in his Gold-Foil experiment?

• He observed that all alpha particles did go through a gold-foil in straight lines

• He observed that most alpha particles did not go through a gold-foil and stopped on one side of the gold foil.

• He observed that a small number of alpha particles bounced off the gold-foil at very large angles

• He observed that all alpha particles slightly deflected from the straight line when going through a gold-foil

Choose one of the conclusions that Ernest Rutherford made based on the experimental results of his Gold-Foil experiment

• He concluded that the atom is indivisible

• He concluded that the atom is mostly empty space

• He concluded that the atom has neutrons

• He concluded that the atom is tightly packed with subatomic particles all mixed together

Tags

NGSS.HS-PS1-8

Based on Rutherford's model of the atom, electrons in the atom are located

• inside of the nucleus of the atom

• outside and around the nucleus of the atom

• outside and inside of the nucleus of the atom

Which scientist realized atoms are mostly empty space?

• Dalton
• Thomson
• Rutherford
• Bohr

What results did Rutherford expect to see if the Plum-Pudding model is correct?

• He expected that most of alpha particles would go through a gold-foil and small number of particles would deflect sightly

• He expected that most of alpha particles would not go through a gold-foil and will stop on one side of a foil.

• He expected that most of alpha particles would ricochet back after hitting a gold-foil