Electron Configurations You will need: 1.Your homework from Friday (Quantum Mechanical Model in last week’s packet) 2.Your homework from last night (Electron Configuration Guided Reading in this week’s packet) Anything that you see in white, you should write down

Bohr Model of Hydrogen Zumdahl, Zumdahl, DeCoste, World of Chemistry  2002, page 331 Nucleus Possible electron orbits e e

Bohr Model of Hydrogen Bohr model = epic fail for all other elements e e

The Quantum Mechanical Model

2 parts of an atoms – Nucleus – Electron cloud » Where the probability of finding an electron is high » Drawn as a fuzzy cloud » The cloud is more dense where the probability of finding the electron is high. More likely to find an electron Less likely to find an electron Nucleus Electron cloud

The Quantum Mechanical Model Atomic Orbitals – Space around the nucleus – High probability of finding an electron – Has a specific energy level – Has a specific sublevel » Sublevels have different shapes Further describes where an electron is likely to be found

The Quantum Mechanical Model Atomic orbital shapes: AKA: Angular momentum quantum number S orbital Angular momentum quantum number ( l ) = 0

The Quantum Mechanical Model Atomic orbital shapes: P orbitals Angular momentum quantum number ( l ) = 1

The Quantum Mechanical Model Atomic orbital shapes: D orbitals Angular momentum quantum number ( l ) = 2

The Quantum Mechanical Model Atomic orbital shapes: F orbitals Angular momentum quantum number ( l ) = 3

Think-Pair-Share Turn to your neighbor and… – Explain what an orbital is – List the 4 shapes of atomic orbitals

Vocabulary Quantum numbers: tell us the properties of atomic orbitals and the properties of electrons in the orbitals Principle quantum number – Symbol: n – The energy level that an electron occupies Angular momentum quantum number – Symbol: l – The shape of the orbital Spin quantum number – +1/2 or -1/2 – Spin state of an electron

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 3 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d5 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4 s12

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4 s12 p36

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4 s12 p36 d5

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4 s12 p36 d5 f

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4 s12 p36 d5 f7

Main energy level (n) Sublevels (orbital shape) Number of orbitals per sublevel Number of electrons per sublevel 1s12 2s12 p36 3 s12 p36 d510 4 s12 p36 d5 f714

Electron Configurations Electron configuration: – The arrangement of electrons in an atom The lowest-energy arrangement of the electrons for each element is called the element’s ground-state electron configuration

Rules for writing electron configurations Aufbau principle: – An electron occupies the orbital of lowest- energy first 1s 2s2p 3s3p3d 4s 4p 4d 4f 5s5p5d5f 6s6p6d6f

Rules for writing electron configurations Hund’s rule: – Electrons occupy equal energy orbitals one at the time – The electrons in each orbital have the same spin – School bus rule 2px 2py 2pz

Rules for writing electron configurations Pauli exclusion principle: – Electrons in the same orbital must have different spins 2px 2py 2pz

Think Pair Share Turn to your neighbor and explain the three rules for electron configurations in your own words

Orbital Diagram p. 105 Box = orbital Arrow = electron Up and down arrow = electrons with opposite spins

Electron Notations Orbital notation – Lines (or boxes) represent orbitals – Arrows represent electrons He

Writing Electron Configurations 1. Locate the element on the periodic table

Writing Electron Configurations 2. Determine the number of electrons in the element 1. Locate the element on the periodic table

Writing Electron Configurations 3. Fill in the electrons in the orbital notation diagram starting at 1s (remember the rules) 2. Determine the number of electrons in the element 1. Locate the element on the periodic table

Writing Electron Configurations 4. Write the electron configuration from the completed orbital notation diagram 3. Fill in the electrons in the orbital notation diagram starting at 1s (remember the rules) 2. Determine the number of electrons in the element 1. Locate the element on the periodic table

Writing Electron Configurations 5. Calculate the number of electrons in the electron configuration and make sure it matches what you found in step 2 4. Write the electron configuration from the completed orbital notation diagram 3. Fill in the electrons in the orbital notation diagram starting at 1s (remember the rules) 2. Determine the number of electrons in an atom of the element 1. Locate the element on the periodic table

Orbital Notation Aufbau principle: an electron occupies the orbital of lowest- energy first Li = # of electrons = 3

Electron Notations Electron configurations Written in the following order: 1.Number of energy level 2.Letter of sublevel 3.Number of electrons in each sublevel written as a superscript 1s 2 Energy level Sublevel Number of electrons 1s 2 2s 2 2p 6 Energy levels Sublevels Number of electrons

Electron Configurations Aufbau principle: an electron occupies the orbital of lowest- energy first Li =1

Electron Configurations Aufbau principle: an electron occupies the orbital of lowest- energy first Li =1s

Electron Configurations Aufbau principle: an electron occupies the orbital of lowest- energy first Li =1s 2

Electron Configurations Aufbau principle: an electron occupies the orbital of lowest- energy first Li =1s 2 2

Electron Configurations Aufbau principle: an electron occupies the orbital of lowest- energy first Li =1s 2 2s

Electron Configurations Aufbau principle: an electron occupies the orbital of lowest- energy first Li =1s 2 2s 1 # of electrons = 3

Electron Configurations C = Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin # of electrons = 6

Electron Configurations C = 1 Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 2 Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 2s Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 2s 2 Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 2s 2 2 Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 2s 2 2p Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin

Electron Configurations C = 1s 2 2s 2 2p 2 Hund’s rule: electrons occupy equal energy orbitals one at the time with the same spin # of electrons = 6

Electron Configurations Ca = # of electrons = 20 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 3 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 3p Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 3p 6 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 3p 6 4 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 3p 6 4s Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Ca = 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 # of electrons = 20 Pauli exclusion principle: electrons in the same orbital must have different spins

Electron Configurations Cl = # of electrons = 17

Electron Configurations Cl = 1

Electron Configurations Cl = 1s

Electron Configurations Cl = 1s 2

Electron Configurations Cl = 1s 2 2

Electron Configurations Cl = 1s 2 2s

Electron Configurations Cl = 1s 2 2s 2

Electron Configurations Cl = 1s 2 2s 2 2

Electron Configurations Cl = 1s 2 2s 2 2p

Electron Configurations Cl = 1s 2 2s 2 2p 6

Electron Configurations Cl = 1s 2 2s 2 2p 6 3

Electron Configurations Cl = 1s 2 2s 2 2p 6 3s

Electron Configurations Cl = 1s 2 2s 2 2p 6 3s 2

Electron Configurations Cl = 1s 2 2s 2 2p 6 3s 2 3

Electron Configurations Cl = 1s 2 2s 2 2p 6 3s 2 3p

Electron Configurations Cl = 1s 2 2s 2 2p 6 3s 2 3p 5

Exit Ticket Fill out the worksheet that is being passed out Turn it in when you are finished Begin working on tonight’s homework – Save #4 for tomorrow night

s p d (n-1) f (n-2) 6767 Blocks of the Periodic Table 1s1s1s1s 2s2s2s2s 3s3s3s3s 4s4s4s4s 5s5s5s5s 6s6s6s6s 7s7s7s7s 3d3d3d3d 4d4d4d4d 5d5d5d5d 6d6d6d6d 1s1s1s1s 2p2p2p2p 3p3p3p3p 4p4p4p4p 5p5p5p5p 6p6p6p6p 7p7p7p7p 4f4f4f4f 5f5f5f5f

Electron Notations Noble gas notation – The noble gas that comes before the desired element on the periodic table is written in brackets – The rest of the electron configuration is written at the end Energy level Sublevel Number of electrons Sodium’s noble gas notation: [Ne]3s 1 Noble gas Energy level Sublevel Number of electrons

Electron Configurations Fe = 1s

Electron Configurations Fe = 1s 2

Electron Configurations Fe = 1s 2 2

Electron Configurations Fe = 1s 2 2s

Electron Configurations Fe = 1s 2 2s 2

Electron Configurations Fe = 1s 2 2s 2 2

Electron Configurations Fe = 1s 2 2s 2 2p

Electron Configurations Fe = 1s 2 2s 2 2p 6

Electron Configurations Fe = 1s 2 2s 2 2p 6 3

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6 4

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6 4s

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d

Electron Configurations Fe = 1s 2 2s 2 2p 6 3s 2 3p 6 4s 2 3d 6 Pauli exclusion principle: electrons in the same orbital must have different spins