Atomic Structure and Models

The video explores the evolution of atomic theory, starting with ancient Greek philosophers Aristotle and Democratus. Aristotle believed matter could be divided infinitely, while Democratus proposed the concept of indivisible atoms. John Dalton later developed a model of atoms as indivisible particles forming elements and compounds. JJ Thompson discovered the electron, leading to the Plum Pudding model, which was later tested by Ernest Rutherford. The video highlights the progression of atomic models and the experiments that shaped our understanding of atomic structure.

What is the common visual representation of an atom?

• A cube with electrons at the corners

• A solid sphere

• A flat disc

• A large nucleus with orbiting electrons

What did Democratus believe about the divisibility of matter?

• Matter cannot be divided at all

• Matter is made of continuous waves

• Matter can only be divided until reaching the smallest particle

• Matter can be divided infinitely

Who disproved Aristotle's theory about matter?

• JJ Thompson

• John Dalton

• Niels Bohr

• Ernest Rutherford

According to Dalton, what is true about atoms of the same element?

• They are exactly the same

• They can be divided into smaller parts

• They have different weights

• They are different in size

What did JJ Thompson discover using a cathode ray tube?

• Protons

• Neutrons

• Electrons

• Photons

What was the Plum Pudding model?

• A nucleus surrounded by empty space

• A solid sphere with no internal structure

• Electrons embedded in a positive sphere

• Electrons orbiting a nucleus

What did Thompson conclude about the mass of electrons?

• They are massless

• They are heavier than hydrogen atoms

• They are almost 2,000 times lighter than hydrogen atoms

• They have the same mass as protons

What was the significance of Rutherford's experiments?

• They discovered the neutron

• They challenged the Plum Pudding model

• They disproved the existence of electrons

• They confirmed the Plum Pudding model

Who was a student of JJ Thompson and conducted further tests on the atomic model?

• Albert Einstein

• Marie Curie

• Niels Bohr

• Ernest Rutherford

What did Rutherford's lab use to test the Plum Pudding model?

• A beam of positively charged particles

• A cathode ray tube

• A laser beam

• A magnetic field