2.2.1 - Electron Structure Flashcards
Definition of the 1st ionisation energy
-the energy required to remove one electron from each atom in one mole of gaseous atoms
What is ‘successive ionisation energy?’
-the energy required to remove each electron in turn
What are the 3 things that ionisation energies can be affected by?
- positive nuclear charge
- electron shielding
- distance from the nucleus
Describe how positive nuclear charge affects IE
- the more protons there are in the nucleus, the more positively charged the nucleus is, so the electrons are more attracted to it
- so higher IE to remove one electron
Explain how electron shielding affects IE
- with an increase in electrons, there is a lower ionisation energy
- this is due to there being a lower attraction between the electron and nucleus as the inner electrons shield it
Explain how distance from the nucleus affects IE
- closer electrons will be more strongly attracted than the ones further away
- so larger atoms with more shells will have lower IE
How many electrons do the first 4 shells hold?
N=1 = 2
N=2 = 8
N= 3 = 18
N=4 =32
What is an orbital?
A region that can hold up to 2 electrons, with opposite spins
Describe the shapes of s and p orbitals
S are spherical
-P orbitals are in the shape of dumb-bells
How many electrons are there in s, p, d and f orbitals?
- S is 2 electrons= 1 orbital
- P is 6 electrons= 3 orbital
- D is 10 electrons= 5 orbitals
- F is 14 electrons = 7 orbital
Describe the Quantum Theory
- energy exists in fixed amounts called quanta
- electrons have to exist in fixed energy levels
- main energy levels are given a principal quantum number (n)
How to write the electronic configuration of ions?
-add or subtract approp. Number of electrons
E.g O2- = 1s^2, 2s^2, 2p4 but add 2 electrons so 2p^6
