Study design

[lachymm]

I was going through it:
"explain the production of atomic absorption and emission spectra, including those from metal
vapour lamps;
• interpret spectra and calculate the energy of photons absorbed or emitted, ΔE = hf;
• analyse the absorption of photons by atoms in terms of
– the particle-like nature of matter
– the change in energy levels of the atom due to electrons changing state
– the frequency and wavelength of emitted photons, E = hf = hc/λ
(not including the bombardment of atoms by electrons);
• describe the quantised states of the atom in terms of electrons forming standing waves, recognising
this as evidence of the dual nature of matter;
• identify and apply safe and responsible practices when working with light sources, lasers and
related equipment."

I am pretty fine with all of it apart from the last 2, I have never even seen the last one :S

The second last dot pointi always have trouble explaining, does anyone have any quick notes i can put on my cheat sheet about the quantised states of the atom?

[Chavi]

For the second last point, you just have to understand that electrons can exist only in discrete energy states. Standing waves just symbolize that electrons exhibit both wave and particle behavior around the nucleus (because as particles they exhibit resonance - which is a distinctly wave-like behaviour.)

AS for the last point, I don't think you have to worry about it. It is highly unlikely a question will come up on safety in physics - but if it does, all you need is common sense - i.e. "do not look directly into the laser. This may cause irreversible eye damage" - etc. . .