Electron Configuration

Question 1

Electron shells (N)

Answer 1

Max number of shells is 7

One per period in the table

Question 2

Sub-Shells

Answer 2

Are within shells S P D F-
1shell = S sub-shell
2shell= S and P sub-shells
3shell= S, P, D sub-shells
4shell= S, P, D,F ,sub-shells- same for 567 shells

Question 3

Sub shell occupancy

Answer 3

S=2 electrons
P=6
D=10 -transition
F=14-innertransition

Question 4

Auf Bau Principle

Answer 4

Electrons are added in order of increasing energy

Question 5

Order of Sub-shells

Answer 5

1S2,2S2,2P6,3S2,3P6,4S2,3D10,4P6,5S2,4D10,5P6,6S2,4F14,5D10,6P6,7S2,5F14,6D10,7P6
n1= 1s. 1s
N2= 2s 2p 2s. 2p.
N3= 3s 3p. 3s. 3p. 3d.
N4= 4s 3d 4p. 4s. 4p. 4p. 4f
N5= 5s 4d 5p. 5s. 5p 5d 5f
N6= 6s 4f 5d 6p. 6s. 6p 6d. 6f
N7= 7s 5s 6d 7p 6f. 7s. 7p

Question 6

Abbreviated Electron Configuration

Answer 6

Write electron iconfiguration relative to noble gas before it
Ex: 19K = [Ar] 4s1

Question 7

UnexpectedElectron Configuration

Answer 7

Half-filled and completely filled d-subshells are especially stable
( favorable)
D subshell always has to be filled evenly
Ex: 29Cu- [Ar]4s2,3d9 -predicted
[Ar]4s2, 3d10-actual

Question 8

Orbital Diagram

Answer 8

Each sub-shell has orbitals , each orbital hold up to 2 electrons
S Sub-shell has 1 orbital- S orbital (spherical shape) 1x2=2
P has 3 orbitals-Px, Py, Pz. 3x2=6
C has 5 orbitlas-Dxy,Dxz,Dyz, Dx2-y2, Dz2. 5x2=10
F has7 orbitals. 7x2=14

Question 9

Rules for writing orbital diagrams

Answer 9

Use arrows to indicate electrons, circles to indicate orbitals
Add electrons to orbitals in order of increasing energy=auf-bau
Max number of electrons is 2;Electrons that share same orbital must have opposite spin

Question 10

Pauli exclusion principle

Answer 10

1-max # of occupancy is 2 electrons per orbital

2- spins must be paired and opposite

Question 11

Hund’s Rule

Answer 11

When electrons are added to orbitals within the same sub-shell, each orbital must get one electron before any orbital gets two electrons

Question 12

Paramagnetism

Answer 12

Element contains unpaired electron spin and therefore weakly attracted to magnets
-unfinished orbitals

Question 13

Diamagnetism

Answer 13

Evenly filled orbitals, like helium

All electron spins are shared

Question 14

atomic size

Answer 14

Atoms get smaller as you go up ( decreasing shells) and right (increasing atomic number) of the periodic table
-the more protons the more, the more attraction to electrons, the smaller the atom. More tightly with positive force
Cations are smaller than parent atoms
Anions are bigger than parent atom

Question 15

Halogens

Answer 15

Group VII A , F, Cl, Br, I, At.