3.1.1.3 Electron Configuration Flashcards
What is the most accepted theory regarding electron shells?
Electrons have a fixed energies
Each shell is give a principal quantum number that contains 4 differenct sub-shells inside of them
What are the names of the 4 sub-shells?
S, D, P and F
What is the maximum electron capacity and number of orbitals of the S sub-shell?
2 electrons and 1 orbital
What is the maximum electron capacity and number of orbitals of the P sub-shell?
6 electrons and 3 orbitals
What is the maximum electron capacity and number of orbitals of the D sub-shell?
10 electrons and 5 orbitals
What is the maximum electron capacity and number of orbitals of the F sub-shell?
14 electrons and 7 orbitals
What is Sub-shell notation?
It is a method of showing the amount of electrons in a element by showing the : energy level, sub-shell and number of electrons
What is the Sub-shell notation of Neon (10 electrons)?
1s2 2s2 2p6
What is the nobel gas shortening of Calcium (Ar is the closest nobel gas)
[Ar] - 4s2
Why doesn’t Chromium and Copper follow the pattern of Sub-shell notation?
- Half a sub-shell is more stable
- Therefore one electron from the 4s sub-shell jumps to the 3d subshell
What is the electron configuration of Cr?
[Ar] - 4s1 3d5
What is the electron configuration of Cu?
[Ar] - 4s1 3d10
During the ionisation of transition metals, where do we remove electrons from?
From the 4s orbital
What are the two methods of showing electron configuration?
Arrows in boxes and Sub-shell notation
What is Arrows in boxes?
Each electron represent an arrow and the direction its pointing is where it the dirrection it is spinning in.
What are the main rules in Arrows in boxes?
- Electrons always fill the lowest energy levels
- Electrons fill orbitals singly before they start sharing
What is the defonition for First Ionisation energy?
The first ionisation energy is the energy required to remove 1 electrom from each element in 1 mole of gaseous atoms to form 1 mole of gaseous 1+ ions
What are the main rules in a First Ionisation energy reaction?
- Gas state symbol is always shown
- Always refer to 1 moole of atoms
- Lower ionisation energy, easier to for m positive ion
What are the three main factors affecting ionisation energy?
- Nuclear Charge
- Distance from the nucleus
- Shielding
How does Nuclear Charge affect ionisation energy?
- The more protons the more attracted the electron is to the nucleus
How does the Distance of electrons from the nucleus affect ionisation energy?
Decreases
- Attraction falls quickly with distance
- The further away electron the less attracted they are
How doe Shielding affect ionisation energy?
As number of electrons between the outermost electron and nucleus increases, the attraction decreases
- This is due to the inner electron shells lessing the force of attraction
What is the second ionisaiton energy?
The second ionisation energy is the energy needed to remove an electron from each ion in 1 mole of gaseous 1+ ions.
What is the equation for the second ionisation energy?
O+1 (g) –> O+2 (g) + e-
What happens to the ionisation energy of Group 2?
Decreases as you go down the group
Why does the ionisation energy of group 2 decrease?
Atomic radius increases so the outermost electron is further away making the attractive force weaker so less energy is required.
Shielding increases due to there being more shells therefore the attractive force is weaker meaning the energy required is less
What happenes to the ionisation energy of Period 3?
Increases as you go across
Why does the ionisation energy of period 3 Increase?
There is a greater nuclear charge therefore more nuclear attraction and shielding is similar so more energy is required to remove electrons
What is the exception when it come to ionisation energy in period 3?
Sulfur has a smaller ionisation energy due to electron-electron repulsion due to them being in the same electron shell
