Ionisation Energies Flashcards
How are orbitals filled?
An electron will always full the available orbital of the lowest energy
Each orbital can hold a maximum of 2 electrons
Atomic orbital of the same energy will singly fill with electrons of the same spin before pairing of electrons occurs
What happens when 2 electrons are in one orbital?
They have opposite spins:
One goes one way
The other goes the opposite
What is the most stable form of sublevel?
One which is exactly half filled is more stable than a partially filled one
Which elements are anomalies from the normal structure of sublevels?
Chromium (Cr)
Copper (Cu)
They take an electron from the 4s orbital and place it in the 3d one
What is the first ionisation energy?
The energy require to remove one mole of electrons from one mole of atoms in its gaseous state
Why is log10 IE plotted instead of the ionisation scale?
The values would be too great/far apart to plot on a graph
With a log10 scale it allows clear visuals and easier values to plot
What are the main significance features on a IE graph and why?
For each successive electron removed more energy is needed - they are closer to the Nucleus so harder to extract
Between 2-3, 10-11, 18-19 there is a significant increase - moves to a different energy shell
What happens to the IE trend across period 3?
There is an increasing nuclear charge (more protons)
Al-Mg: Al’s outer electron is in a 3p orbital which needs less energy to remove than a 3s one
P-S: in P each 3p electron occupies a different 3p orbital. In S one 3p orbital must contain 2electrons - they repel making them easier to remove
What happens to the trend in IE as you go down group 2?
It’s decrease
Nucleus is shielded by the inner shells
The outer electron is significantly further from the nucleus
