Development of the Model of the Atom

The video explores the historical development of atomic theory, starting with Democritus' concept of indivisible atoms. It covers the discovery of the electron by JJ Thompson using cathode ray tubes, leading to the plum pudding model. Rutherford's gold foil experiment revealed the nucleus, altering the atomic model. Bohr further refined the model with defined electron orbits, and Chadwick discovered the neutron, completing the modern understanding of atomic structure.

Who was the first to propose the idea of the atom as an indivisible particle?

• Plato

• Democritus

• Socrates

• Aristotle

What was the first subatomic particle to be discovered?

• Photon

• Electron

• Neutron

• Proton

Which scientist used cathode ray tubes to discover the electron?

• Niels Bohr

• Ernest Rutherford

• James Chadwick

• JJ Thompson

What did Rutherford's gold foil experiment demonstrate about the structure of the atom?

• Atoms are indivisible.

• Electrons are embedded in a positive substance.

• Atoms are mostly empty space with a dense nucleus.

• Atoms are solid spheres.

What model of the atom was disproved by Rutherford's experiment?

• Quantum model

• Solid sphere model

• Plum pudding model

• Bohr's model

What did Niels Bohr propose about electron movement in atoms?

• Electrons are embedded in a positive matrix.

• Electrons are randomly distributed.

• Electrons orbit the nucleus in defined paths.

• Electrons are stationary.

Who discovered the neutron, completing the modern atomic model?

• JJ Thompson

• James Chadwick

• Niels Bohr

• Ernest Rutherford