alcalder said:
Heisenberg also proposed that there were protons and neutrons in the nucleus and not protons and electrons (1932).
shit are u sure? I thought it was Pauli's exclusion principle who said that electrons cant exist in the same quantum state (i.e. in nucleus) and that it was Rutherford who in 1920 suggested the existence of a neutron, because the mass of the nucleus was found to twice that of the atomic number (amt of protons)
Mshell said:
What do we need to know about Heisenberg and Pauli? Apart from the uncertainty principle and the exclusion principle.
Ok some essentials.
Heisenberg first
By 1924 it was widely accepted that a new more encompassing theory of quantum mechanics would be needed to explain the drawbacks and faults of Bohr's model of the atom (couldnt explain anomalous zeeman effect, relative intensities of spectra etc).
and in 1925 Heissenberg contributed a new quantum theory (whos details are not in the scope of the syllabus) by using complex mathematical constructs known as
matrices. So thats a big one, other than that itd just be the Uncertainty Principle.
However you'd have to go into the
implications of the uncertainty principle, and its contribution to the quantum theory, because classical physics has assumed that at any one time the position and momentum of a particle (at subatomic level) could be determined. The uncertainty principle reflects the very nature of quantum theory,
nothing is certain, the quantum theory is
non-deterministic and we have to now consider the
probability of an event as opposed to the
certainty of an event.
Pauli- just what alcalder said, and the exclusion principle itself, which enabled the elucidation of the periodic table (enabling us to determine the electronic configuration of each atom). He also employed the quantum number of integer spin, which was able to explain the anomalous zeeman effect etc.