2.2.1 Electron structure Flashcards
1
Q
what is the principal quantum number n also known as
A
- the shell number or energy level number
2
Q
what increases as the shell number increases
A
- energy
- further the shell is from nucleus
3
Q
what are shells made up of
A
- atomic orbitals
4
Q
what is an atomic orbital
A
- a region around the nucleus that can hold up to 2 electrons with opposite spins
> its a region in space where there is a high probability of finding an electron
5
Q
what are the different types of orbitals
A
s-
p-
d-
f-
6
Q
in an s subshell how many s orbitals are there
A
- 1 x s orbital
7
Q
in a p subshell how many p orbitals are there
A
- 3 x p orbitals
8
Q
in a d subshell how many d orbitals are there
A
- 5 x d orbitals
9
Q
in an f subshell how many f orbitals are there
A
- 7 x f orbitals
10
Q
what does the first shell n=1 contain
A
- 1s orbital
- 2 electrons
- 1 orbital overall
11
Q
what does the second shell n=2 contain
A
- 2s orbital + 3 (2p) orbitals
- 8 electrons
- 4 orbitals overall
12
Q
what does the third shell n=3 contain
A
- 3s orbital + 3 (3p) orbitals + 5 (3d) orbitals
- 18 electrons
- 9 orbitals overall
13
Q
what does the fourth shell n=4 contain
A
- 4s orbital + 3 (4p) orbitals + 5 (4d) orbitals + 7(4f) orbitals
- 32 electrons
- 16 orbitals
14
Q
what shape is an s-orbital
A
- spherical shape
15
Q
A
16
Q
how many electrons can an orbital hold
A
- up to 2e-
17
Q
name the 3 rules for filling atomic orbitals
A
- Rule 1: orbitals fill in order of increasing energy
- Rule 2: electrons pair with opposite spins
- Rule 3: orbitals with the same energy are occupied slightly first
18
Q
why do electrons pair with opposite spins
A
- electrons repel each other
- electrons have a property called spin - either up or down
- 2 electrons in an orbital must have opposite spins to minimise the repulsion between them
19
Q
why do orbitals with same energy occupied singly first
A
- this prevents repulsion between paired electrons until there is no further orbitals available at the same energy level
