Idenitfy Key Discoveries

Q1: Which of the following scientists discovered the atom?

Incorrect - Bohr discovered electron shells
Well done! Dalton is one of the founders of chemistry.
Sorry - Geiger helped Rutherford to discover the nucleus and protons.

Identify Key Discoveries

Q2: Who discovered electrons?

Well done - JJ Thomson was the first to prove that atoms contain smaller particles.
Incorrect - Bohr discovered electron shells. Close!
Incorrect - Dalton discovered atoms.

The Plum Pudding Model

Q3: Which of these statements best describes the Plum Pudding model.

Incorrect - this is a perfect description of Rutherford's Nuclear model.
Incorrect - JJ Thomson proved that atoms can be broken apart by splitting electrons off!

The Nuclear Model

Q4: Why is this statement incorrect? Rutherford proved that atoms contain a small dense nucleus full of protons and neutrons. This is surrounded by a diffuse (spread out) cloud of electrons. He demonstrated that over 99% of an atom is empty.

Well done - neutrons were the last sub-atomic particle to be discovered.
Incorrect - the discovery of electron shells came around 20 years later.
Afraid not - This idea was proven incorrect by Thomson's discovery of the electron.


Q5: Why were neutrons the last part of the nuclear model to be discovered?

Incorrect - electrons are the sub-atomic particle with almost no mass.
Incorrect - they're pretty chunky!
Correct - they're neutral, this means they don't tend to interact with other particles. It's hard to discover something that just sits there chilling out.
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