The video explores the evolution of atomic theory, starting with Democritus's idea of 'atomos' and Aristotle's four elements. It covers Dalton's experiments leading to the law of multiple proportions and the concept of atoms as solid spheres. Thomson's cathode ray experiments introduced the 'plum pudding' model, which was later challenged by Rutherford's gold-foil experiment, revealing a nucleus. Bohr introduced quantized energy levels to explain atomic stability, while Schrödinger's quantum mechanical model described electrons as clouds, incorporating wave-particle duality and the uncertainty principle.

Who proposed that everything in the world was made of tiny indestructible particles called 'atomos'?

• Aristotle

• J.J. Thompson

• Democritus

• John Dalton

What did Aristotle believe everything on this planet was made of?

• Four elements: earth, fire, water, and air

• Atoms

• Energy

• Molecules

What did John Dalton observe when he mixed two gases?

• They exploded

• They formed a liquid

• They did not react at all

• They reacted in a fixed ratio

What law did John Dalton's experiments give rise to?

• Law of Conservation of Mass

• Law of Definite Proportions

• Law of Universal Gravitation

• Law of Multiple Proportions

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What did J.J. Thompson use to discover the electron?

• Oil drop experiment

• Cathode ray tube

• X-ray diffraction

• Gold-foil experiment

What was the name of J.J. Thompson's atomic model?

• Quantum Mechanical Model

• Plum Pudding Model

• Solar System Model

• Nuclear Model

What did Rutherford discover about the structure of the atom?

• Atoms are indivisible

• Atoms have a positively charged nucleus

• Atoms are made of four elements

• Atoms are solid spheres

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What experiment did Rutherford use to probe the structure of an atom?

• Gold-foil experiment

• Oil drop experiment

• Cathode ray tube experiment

• X-ray diffraction

What did Niels Bohr propose about electron movement?

• Electrons move randomly

• Electrons move in fixed orbits or shells

• Electrons are stationary

• Electrons move in a straight line

According to Schrödinger, where are electrons most likely to be found?

• In the outer space

• In the nucleus

• In electron clouds within atomic orbitals

• In fixed orbits