S1.3 Electron Configurations

Electron config.

S1.3.1 EM spectrum

Range of f’s carrying all EM-radiation & their E and λ.

Devided into regions; radio, micro, infra,visual, uv, x, gamma: →^E,f, ←=^λ

Gamma, x, uv dangerous (high f/E)

(c=speed light)c=λf. E = hf (h=planks)

f = waves/second, λ = distance between 2 consecutive peaks.

S1.3.2 Continuous vs line emmission spectra

Continuous: all colours; red→purple
Line: only certain λ: e^- have quantines E, non continuous so see certain

Emmission: e^- move around nucleus rapidly in energy cells: further = more E. When excited; bc of stimulus like light shining on it, move up an energy level; then immidiately move down; releasing energy in the form of a photon; photon carries specific amount of energy, the energy it emits has a specific λ, which is seen on the line emmission spectrum. The emitted photon is of the same energy as the one it initially absorbed.

Absorption spectrum: shows rainbow - black lines
Emmission spectrium: Shows black screen + rainbow lines
Use spectrometer to measure stuff…

As higher E-level; energies closer and closer, so blue end more convergent lines

Max E = ionization energy: from n=1,2,3 → n=infinity: leave atom

n_infin→n=3: IR, n_infin→n=2: visible, n_infin→n=1: UV

S1.3.3 Electron configuration

= The arrangement of electrons. Around nucleus in principal energy levels/quantum shells of discrete energies. Nr of available spots for e^- per nucleus = 2,8,18,32: 2n²… Subshells: s,p,d, E increases
s carries 1 pair(2e), p carries 3 pairs(6e), d carries 5 pairs(10e).

Subshell = orbitals: specific E levels; e is found here, nowhere else

S=round, P=dumbell (x,y,z), D=weird whatever.

Ground state = most stable config. & lowest E: Aufbau: fill 1s, then 2s, then 2p etc…. 4s has lower E than 3d so fill first, then 4p etc.
EXCEPT: Cr: 3d⁵4s¹ and Cu 3d¹⁰4s¹ (energetically more favorible)

1s²2s²2p⁶……., shorten using noble gases: [Ne]3s² blabla

Hund’s rule: 1^st fill up 1 per orbital:[1][1][1] instead of [1I][1][ ] → bc of spin pair repulsion: one north one south: so prefer to seperate

Pauli Exclusion: hold 2 only, opposing spins

Diagrams like up for more E and to the right n shit….

S1.3.4 Ionization Energies

Energy required to ionize an atom/remove an electron: X → X⁺ + e^-

for hydrogen, E = ^13.6/_n² where n is the initial energy level lalala

In kJ mol^-1. Succesive IE of element : increase in general: nuclear charge pull in. Big change = change of shell (1,2,3), small change = change of orbital (s,p,d)

1st IE: increase as you move up periodic table: increase to right too: atom rad, inner e repuls, nuclear charge, spin pair repulsion
Radius: increase: down group, to left, inner shield: same perio, increase down