Nuclear Flashcards
Who created the Billiard Ball Model? When?
Dalton in the 1800s
What were the issues with the Billiard Ball Model?
How and why molecules are formed and held together.
What did the Billiard Ball Model explain?
All matter is made of atoms. Atoms are the smallest particles of matter. There are no subatomic particles.
Who created the Plum Pudding Model? When?
Thompson in 1897
Who came up with ‘electron’?
The negative particles inside the cathode rays were called electrons by Thompson.
What did the Plum Pudding Model explain?
This explained that electrons were smaller than atoms. (Same as Dalton but only realized the existence of electrons)
Who came up with the Nuclear Model? When?
Rutherford in 1911
Who used the scattering of alpha particles as evidence? What did it explain?
The scarring of alpha particles in various gases allowed Rutherford to prove that the nucleus is positive.
What was the issue with the Planetary Model?
It did not explain the EMR radiation that electrons should be giving off. Plus, if electrons are orbitting in this way then they would collide with the nucleus due to centripetal force.
Who came up with the Energy Level Model? When?
Niels Bohr in 1913
What assumption did Bohr make about the electron’s orbit?
The electron occupies only certain regions of space rather than orbitting all around.
What are some issues with Rutherford’s Planetary model?
electrons should emit EMR and the bright line spectrum of gasses issue
When do electrons emit radiation?
They emit radiation when they move down a level
Which spectrum do hot gasses emit?
Continous Spectrum
Which spectrum does only light produce?
Continous Spectrum
