Structure 1.3 - Electron Configuration

Question 1

what is the lowest energy level also known as?

Answer 1

the K shell
closest to the nucleus

Question 2

principle quantum number

Answer 2

main energy level number - n
2n^2 - max no. of electrons in each shell

(1.3.3)

Question 3

what are sub-shells?

Answer 3

each main energy level is split up into sub-energy levels

Question 4

how many sub shells in main energy level 1?

Answer 4

1s sub level (1)

Question 5

how many sub shells in main energy level 2?

Answer 5

2s and 2p sub levels (2)

Question 6

how many sub shells in main energy level 3?

Answer 6

3s, 3p and 3d sub levels (3)

Question 7

how many sub shells in main energy level 4?

Question 8

what is an orbital?

Answer 8

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

Question 9

what is an s orbital?

Answer 9

lowest energy level
- smallest orbital
- only 1 shape
- holds 2 electrons
- spherical
- size of the s orbitals increases with increasing shell number

Question 10

what is a p orbital?

Answer 10

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

Question 11

what is a d orbital?

Answer 11

has 5 shapes
holds 10 electrons altogether

Question 12

what is an f orbital?

Answer 12

has 7 shapes
holds 14 electrons

Question 13

order of electron config

Answer 13

1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p

Question 14

what is the ground state?

Answer 14

the most stable electronic configuration of an atom which has the lowest amount of energy

Question 15

what is the Aufbau Principle

Answer 15

electrons enter orbitals from the lowest energy level first

(1.3.5)

Question 16

what is the Pauli exclusion principle?

Answer 16

an orbital can only hold 2 electrons with opposite spins

Question 17

what is Hund’s rule?

Answer 17

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.

Question 18

what is the electron config for oxygen?

Question 19

what is the e.c for sodium?

Question 20

what is the e.c for cobalt?

Question 21

why are chromium and copper exceptions?

Question 22

which groups are in the s block?

Answer 22

group 1 and 2
- s orbitals are being filled

Question 23

which groups are in the p block?

Answer 23

group 13-18
- p orbitals are being filled

Question 24

what groups are in the d block?

Answer 24

transition metals

Question 25

what is a transition metal?

Answer 25

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.

Question 26

electronic structure of group 1 elements?

Answer 26

ns^1

Question 27

electronic structure of group 2 elements?

Answer 27

ns^2