Atomic Structure Flashcards
Evolution of the atomic structure
1) Dalton- solid spheres
2) JJ Thompson- Plum Pudding Model
3) Rutherford- Nuclear Model, nucleus surrounded by a cloud of electrons
4) Bohr- Fixed orbitals at fixed energies, EM Radiation emitted when e- move between shells
What does Mr stand for?
Relative formula mass
What does Ar stand for?
Relative atomic mass
Exceptions in electron configuration
Chromium and Copper
In order the half fill the orbital (Cr) or fill the orbitals (Cu) due to electron repulsion in order to make themselves more stable, the 4s orbital empties before the 3d
How do electrons interact in orbitals
Electrons fill orbitals before sharing them due to electron repulsion
What is electrospray Ionisation and how does it work
A sample is dissolved in a solvent
It is then pushed through a nozzle at a high pressure and high voltage
It gains a H+
The solvent is removed and only the gas remains
What is Electron impact and how does it work
The sample is vaporised Electrons are shot at a high velocity An electron is knocked off H+ ions are created May cause fragmentation
How are ions accelerated in Time Of Flight
They are accelerated by an electric field
Is there an electric field during ion drift in Time Of Flight
No
General trend in successive Ionisation
Increases
What are the discrepancies in Ionisation succession trends
First-
3rd shell, weakly attracted
Between 2 and 9-
8e- from 2nd shell= closer to the nucleus= increased attraction
Between 10 and 11-
2e- from first shell, closest to nucleus therefore very difficult to remove
Is Ionisation endothermic or exothermic
Endothermic
Factors affecting Ionisation energy
Nuclear charge or protons (Period)
Shielding (group)
Distance from nucleus
Ionisation energy across period 3
Third ionisation (Aluminium)
Sixth Ionisation
(Sulphur)
Electron repulsion makes their electrons easy to lose because electrons are more stable when they don’t share an orbital
