Subatomic Particles and Atomic Models

The video explores the discovery of subatomic particles, starting with early atomic theories by John Dalton, followed by J.J. Thompson's cathode ray experiments that led to the discovery of electrons. Robert Millikan's oil drop experiment determined the electron's charge and mass. Thompson's plum pudding model is discussed, which was later challenged by Ernest Rutherford's gold foil experiment, revealing the nucleus. Finally, James Chadwick's discovery of neutrons is covered, highlighting their role in atomic structure.

What was the main belief about atoms according to Dalton's atomic theory?

• Atoms have a nucleus.

• Atoms are made up of electrons and protons.

• Atoms are indivisible and indestructible.

• Atoms can be divided into smaller particles.

What did J.J. Thompson discover through his cathode ray experiments?

• Protons

• Neutrons

• Electrons

• Nucleus

What was the significance of Millikan's oil drop experiment?

• It determined the charge of the proton.

• It proved the existence of the nucleus.

• It discovered the neutron.

• It measured the charge and mass of the electron.

In the plum pudding model, how are electrons distributed?

• Electrons are spread evenly through positive charge.

• Electrons orbit the nucleus.

• Electrons are concentrated in the center.

• Electrons are paired with protons.

What did Rutherford's gold foil experiment reveal about the atom?

• Atoms are solid spheres.

• Atoms have a dense, positively charged nucleus.

• Atoms are made only of electrons.

• Atoms have no empty space.

What did James Chadwick discover about the atom?

• The existence of protons.

• The presence of electrons.

• The neutron as a neutral subatomic particle.

• The structure of the nucleus.

What role do neutrons play in the nucleus?

• They attract electrons.

• They repel protons.

• They determine the charge of the nucleus.

• They act as a buffer to prevent proton repulsion.

Which subatomic particle has essentially no mass in calculations?

• Electron

• Neutron

• Nucleus

• Proton

How are the charges of protons and electrons related?

• They are both positive.

• They are both negative.

• They are equal and opposite.

• They are neutral.

If the nucleus were the size of a marble, how large would the entire atom be?

• The size of a basketball

• The size of a baseball

• The size of a football field

• The size of a tennis court