Practice Questions James Chadwick Contribution to Atomic Theory

Who led the research that concluded atoms contain a particle with mass but no charge?

• Niels Bohr

• Albert Einstein

• James Chadwick

• Ernest Rutherford

What name was given to the particle with mass but no charge discovered within atoms?

• Proton

• Neutron

• Photon

• Electron

What observation indicated the existence of an additional particle within atoms, besides protons and electrons?

• Atoms are indivisible.

• The mass of atoms is equal to the sum of the masses of their protons and electrons.

• Atoms can emit a stream of particles affected by magnetic fields.

• The mass of atoms is greater than the sum of the masses of their protons and electrons.

What property of the stream of particles emitted by atoms suggested the existence of the neutron?

• They could be split into smaller particles.

• They were unaffected by magnetic or electric fields.

• They were negatively charged.

• They were positively charged.

What was the significance of James Chadwick's conclusion about the neutron?

• It showed that electrons are the only particles within atoms.

• It disproved the existence of atoms.

• It explained the observed atomic mass discrepancy and behavior of certain particle streams.

• It proved that protons could exist outside the nucleus.

How did the discovery of the neutron alter the atomic model?

• It introduced the concept of isotopes.

• It led to the understanding that atoms are mostly empty space.

• It confirmed the plum pudding model.

• It necessitated the revision of atomic mass calculations.

What role do neutrons play in the nucleus of an atom?

• They generate electrical charge.

• They contribute to the mass and stability of the nucleus.

• They orbit the nucleus, balancing the protons.

• They are involved in chemical reactions between atoms.

Which experiment led to the discovery of the neutron?

• Gold foil experiment

• Cathode ray tube experiment

• Beryllium experiment

• Oil drop experiment