Exploring the Discovery of the Neutron

What particles are found in the nucleus of an atom?

• Only protons

• Neutrons and electrons

• Protons and neutrons

• Electrons and protons

Tags

NGSS.HS-PS1-8

Which experiment indicated the presence of protons in the nucleus?

• Chadwick's experiment

• Bohr's model

• Gold foil experiment

• Thomson's experiment

What was one clue that suggested the existence of neutrons in the nucleus?

• The repulsion between protons

• The attraction between electrons

• The mass of electrons

• The charge of protons

Tags

NGSS.HS-PS1-8

Why did scientists think there was something else in the nucleus besides protons?

• Because the atom was unstable

• Because the atom had no charge

• Because the atom was too heavy

• Because the atom was too light

Tags

NGSS.HS-PS1-8

What did scientists discover when comparing the masses of hydrogen and helium?

• Hydrogen and helium had the same mass

• Hydrogen was heavier than expected

• Helium was lighter than expected

• Helium was heavier than expected

Who discovered the neutron?

• James Chadwick

• Niels Bohr

• Ernest Rutherford

• J.J. Thomson

What particles did James Chadwick shoot at atoms to discover neutrons?

• Gamma rays

• Protons

• Alpha particles

• Beta particles

What was the key observation in Chadwick's experiment that led to the discovery of neutrons?

• Atoms were split

• Neutral rays were emitted

• Electrons were emitted

• Protons were deflected

What did the emitted neutral rays in Chadwick's experiment do when they hit paraffin?

• Released alpha particles

• Released protons

• Released neutrons

• Released electrons

What are the three subatomic particles that make up an atom?

• Protons, electrons, and positrons

• Protons, neutrons, and photons

• Protons, neutrons, and electrons

• Neutrons, electrons, and positrons