5.1 - Electron Structure Flashcards
how is the maximum number of electrons in a shell (n) calculated?
2n2
what are shells made up of?
atomic orbitals
what is an atomic orbital?
an atomic orbital is a region around the nucleus that can hold up to two electrons with opposite spins.
it is a region of space where there is a high probability of finding an electron.
what shape is an s-orbital?
sphere
shell 1 of an atom contains which orbital?
1 s orbital
which contains 2 electrons
what shape is a p orbital?
dumbbell
a full shell 2 contains which orbitals?
1 s orbital
3 p orbitals
shell 3 contains which orbitals?
1 s orbital
3 p orbitals
5 d orbitals
which sub-shells are present in shell 2?
2s and 2p
how do orbitals fill?
orbitals fill in order of increasing energy.
within each shell, the new type of sub shell added has a higher energy.
e.g. 2p has a higher energy than 2s, so 2s fills first.
why does the 4s sub-shell fill before the 3d sub-shell?
3d sub-shell has a higher energy than the 4s sub-shell.
so 4s fills first.
why do two electrons in an orbital have opposite spins?
the counteract the repulsion between the negative charge of the two electrons.
what is the energy like within a sub shell?
within a sub-shell, orbitals have the SAME energy.
how do electrons fill orbitals within a sub shell?
one electron occupies each orbital before pairing starts to prevent any repulsion between paired electrons.
what is the same about all elements in the s block?
highest energy electrons in the s sub-shell
