Structure 1.3 - Electron Configuration Flashcards
what is the lowest energy level also known as?
the K shell
closest to the nucleus
principle quantum number
main energy level number - n
2n^2 - max no. of electrons in each shell
(1.3.3)
what are sub-shells?
each main energy level is split up into sub-energy levels
how many sub shells in main energy level 1?
1s sub level (1)
how many sub shells in main energy level 2?
2s and 2p sub levels (2)
how many sub shells in main energy level 3?
3s, 3p and 3d sub levels (3)
how many sub shells in main energy level 4?
what is an orbital?
regions of space where there is a high probability of finding an electron
- represents a discrete energy level
- can contain a maximum of 2 electrons
what is an s orbital?
lowest energy level
- smallest orbital
- only 1 shape
- holds 2 electrons
- spherical
- size of the s orbitals increases with increasing shell number
what is a p orbital?
dumbbell shape at right angles with nucleus at the centre
- 3 p shapes each holding 2 electrons = holds 6 electrons in total
- higher energy level than s
- Every shell has three p orbitals except for the first one (n = 1)
- The p orbitals occupy the x, y and z axes and point at right angles to each other, so are oriented perpendicular to one another
- The lobes of the p orbitals become larger and longer with increasing shell number
what is a d orbital?
has 5 shapes
holds 10 electrons altogether
what is an f orbital?
has 7 shapes
holds 14 electrons
order of electron config
1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p
what is the ground state?
the most stable electronic configuration of an atom which has the lowest amount of energy
what is the Aufbau Principle
electrons enter orbitals from the lowest energy level first
(1.3.5)
what is the Pauli exclusion principle?
an orbital can only hold 2 electrons with opposite spins
what is Hund’s rule?
electrons enter orbitals singly until they have to pair up
electrons fill orbitals of the same energy (degenerate
orbitals) so as to give the maximum number of electrons with the
same spin.
what is the electron config for oxygen?
what is the e.c for sodium?
what is the e.c for cobalt?
why are chromium and copper exceptions?
which groups are in the s block?
group 1 and 2
- s orbitals are being filled
which groups are in the p block?
group 13-18
- p orbitals are being filled
what groups are in the d block?
transition metals
what is a transition metal?
one which has partially filled d orbitals either in the element or any of its compounds.
Zinc (at the right-hand end of the d-block) always has a completely full 3d level (3d10) and so doesn’t count as a transition element.
electronic structure of group 1 elements?
ns^1
electronic structure of group 2 elements?
ns^2
