The locations of electrons (Quantum number) Principal Energy Level (Shells in Bohr model) Energy Sublevel (Probability plots of all orbitals on the x, y, and z axis) Specific Orbitals (Probability specific to the x, y, or z axis) This is like an address for the electron. Principal Level  Energy Sublevel  Orbital Similar to finding where people live. City  Street  House/Apt. #

Orbitals: A region within an energy level where there is a probability of finding an electron. Orbital shapes are defined as the surface that contains 90% of the total electron probability.

The s orbital has a spherical shape centered around the origin of the three axes in space. The s is named for the “sharp” lines in a bright-line spectra. s orbital shape

P orbital shape A p sublevel has 3 orbitals, each assigned to its own axis (x, y and z) in space. “p” orbitals are dumbbell shaped or like a figure 8. “p” is for the principal lines of the bright line spectra.

Shape of d orbitals A d sublevel has 5 orbitals. d orbital shapes A d sublevel has 5 orbitals. The d sublevels begin with principal level n = 3 To remember the shapes, think of “double dumbbells” …and a “dumbbell with a donut”!

Shape of f orbitals

s p f d The locations of electrons. 1. Principal Energy Level. 2. Energy Sublevel (s, p, d, f). 3. Specific Orbitals (s, p, d, f). s p (1 orbital) (3 orbitals) f (7 orbitals) d (5 orbitals)

Combination of s and p

Sizes of s orbitals Orbitals of the same shape (s, for instance) grow larger as n increases… Nodes are regions of low probability within an orbital.

n = 1 1s n = 2 2s, 2p n = 3 3s, 3p, 3d n = 4 4s, 4p, 4d, 4f n = 5 The Principal Energy Level determines the number of sublevels. Principal Energy Level Sublevels available n = 1 1s n = 2 2s, 2p n = 3 3s, 3p, 3d n = 4 4s, 4p, 4d, 4f n = 5 5s, 5p, 5d, 5f, 5g n = 6 6s, 6p, 6d, 6f, 6g, 6h n = 7 7s, 7p, 7d, 7f, 7g, 7h, 7i

Orbital Diagram: f d p s Shows sublevels as lines or boxes. The number of boxes match how many orbitals are in a specific sublevel. (7 orbitals) (5 orbitals) (3 orbitals) (1 orbital) f d p s (1 orbital) (3 orbitals) (7 orbitals) (5 orbitals)

Shows where each sublevel is filling. Orbital filling table s1 s2p1 s2p2 s2p3 s2p4 s2p5 s2 s2 Shows where each sublevel is filling. s2p6 4 s fills before 3d

e- configuration: Three rules for filling e- in the e- cloud. Aufbau Principle: Electrons fill lowest energy levels 1st. Pauli Exclusion Principle: An orbital can only hold two e- and they must have opposite spin. Hund’s Rule: Sublevels with multiple orbitals (p, d, f) must fill orbitals one at a time before doubling up. Example: Neon Z=10 Z = atomic # so … 10 protons = 10 e- Orbital Diagram: 1s 2s 2p e- configuration: 1s2 2s2 2p6

Ne Neon Z=10 Valence Shell e- configuration: Dot Structure: Orbital Diagram: 1s 2s 2p e- configuration: 1s2 2s2 2p6 Dot Structure: Ne Each pair of dots represents a set of arrows (electrons with opposite spin) Shows valence electrons (e- in highest energy level) as dots around the chemical symbol.

N Nitrogen Z = 7 A) orbital  diagram B) electron  configuration 1s2 2p B) electron  configuration 1s2 2s2 2p3 C) Dot diagram 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i N

S Sulfur Z = 16 A) orbital  diagram B) electron  configuration 1s2 2p 3s 3p B) electron  configuration 1s2 2s2 2p6 3s2 3s2 3p4 3p4 S 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i C) Dot diagram

Ga Ga or Gallium Z = 31 A) orbital  diagram B) electron  1s 2s 2p 3s 3p 4s 3d 4p B) electron  configuration 1s2 2s2 2p6 3s2 3p6 4s2 4s2 3d10 4p1 4p1 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i C) Dot diagram Ga Ga or

Predicted Cr Cr or Chromium Z = 24 A) orbital  diagram B) electron  1s 2s 2p 3s 3p 4s 3d B) electron  configuration 1s2 2s2 2p6 3s2 3p6 4s2 4s2 3d4 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i C) Dot diagram Cr Cr or

Irregular configuration Half-filled and filled states preferred Actual Irregular configuration Chromium Z = 24 A) orbital  diagram Half-filled and filled states preferred 1s 2s 2p 3s 3p 4s 3d B) electron  configuration 1s2 2s2 2p6 3s2 3p6 4s1 4s1 3d5 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i C) Dot diagram Cr

Irregular e- configurations of Cr and Cu Chromium steals a 4s electron to half fill its 3d sublevel Copper steals a 4s electron to FILL its 3d sublevel

s (1 orbital) p (3 orbitals)

Pauli Exclusion Principle: Aufbau Principle: e- fill lowest energy levels 1st. Pauli Exclusion Principle: Only 2e- per orbital with opposite spin Hund’s Rule: Sublevels with multiple orbitals fill 1 at a time before doubling up. 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i 4f 5p 4d 5s 4p 3d Increasing energy 4s Notice how 4s fills before 3d 3p 3s Aufbau Diagram 2p 2s Sometime new sublevels fill before previous levels are full. An e- from 4s moves to 3d (half-filled states are preferred) 1s nucleus

K S Al Se Ti Ga O Cu Co Cr Na Li H B Ca Zn F Mn He Be V Ge Mg Br Ni C Aufbau Principle e- fill lowest energy levels 1st. Half-filled and filled states are preferred. 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 5g 6s 6p 6d 6f 6g 6h 7s 7p 7d 7f 7g 7h 7i 4f 5p 4d 5s 4p 3d Increasing energy 4s 3p 3s 19 K Potassium [Ar]4s1 16 S Sulfur [Ne]3s23p4 13 Al Aluminum [Ne]3s23p1 34 Se Selenium [Ar]3d104s24p4 22 Ti Titanium [Ar]3d24s2 31 Ga Gallium [Ar]3d104s24p1 8 O Oxygen 1s22s22p4 29 Cu Copper [Ar]3d104s1 27 Co Cobalt [Ar]3d74s2 24 Cr Chromium [Ar]3d54s1 11 Na Sodium [Ne]3s1 3 Li Lithium 1s22s1 1 H Hydrogen 1s1 5 B Boron 1s22s22p1 20 Ca Calcium [Ar]4s2 30 Zn Zinc [Ar]3d104s2 9 F Fluorine 1s22s22p5 25 Mn Manganese [Ar]3d54s2 2 He Hydrogen 1s2 4 Be Beryllium 1s22s2 23 V Vanadium [Ar]3d34s2 32 Ge Germanium [Ar]3d104s24p2 12 Mg Magnesium [Ne]3s2 35 Br Bromine [Ar]3d104s24p5 28 Ni Nickel [Ar]3d84s2 6 C Carbon 1s22s22p2 14 Si Silicon [Ne]3s23p2 17 Cl Chlorine [Ne]3s23p5 36 Kr Krypton [Ar]3d104s24p6 29 Cu Copper [Ar]3d104s1 33 As Arsenic [Ar]3d104s24p3 24 Cr Chromium [Ar]3d54s1 15 P Phosphorus [Ne]3s23p3 7 N Nitrogen 1s22s22p3 10 Ne Neon 1s22s22p6 26 Fe Iron [Ar]3d64s2 18 Ar Argon [Ne]3s23p6 21 Sc Scandium [Ar]3d14s2 2p 2s 1s nucleus