The Arrangement of Electrons Cont… Part 1 Review and Formative Assessment When finished begin working on Part 2 of packet (pages 111-122)

Today’s Purpose Update Objective 1- Where do you stand? Green Learning Objective Sheet. Update Objective 1- Where do you stand? Plan of Action – Learning Opportunities I can write electron configurations using orbital notation, electron configuration notation, and noble gas notation.

......Thoughts..... Review/Update One’s Understanding… Where are lithium’s electrons located in the atom? Turn to your elbow partner and share your ideas, be prepared to explain to the class.

POGIL : Electron Configurations Clean Sheet of Paper / Notes Label “Electron Configuration POGIL” Work with partner – same face value on card. Expectations: Complete solutions on your note sheet. (Model) Talk through it with your partner. Stay on-task. Be prepared to share out: (Timer on board) Pages 1 & 2: 5 Minutes Pages 3-5 : 10 Minutes Page 6: 5 Minutes

Electron Configuration The arrangement of electrons in an atom. Arrangements in lowest possible energies. Ground-state electron configurations.

Aufbau Principle An electron occupies the lowest-energy orbital that can receive it. Writing electron configurations of atoms by successively filling subshells with electrons in a specific order (the building-up order). You obtain electron configurations by filling the subshells in the following order: 1s, 2s, 2p, 3s, 3p, 4s, 3d, 4p, 5s, 4d, 5p, 6s, 4f, 5d, 6p, 7s, 5f, 6d, 7p Think back to POGIL

Diagonal Rule Order of filling tool. Place on top of note page. Model: Chlorine

Writing Electron Configurations Determine the number of electrons using atomic number from the periodic table. Follow the order listed by Aufbau (Diagonal Rule) to fill out the electron configuration. The superscripts should add up to equal the number of electrons. Ex: Lithium’s Electron Configuration -Lithium has 3 electrons. 1s22s1

More Examples 1. Magnesium’s Electron Configuration -model 2. Carbon’s Electron Configuration- model 3. Iron’s Electron Configuration-partner 4. Bromine’s Electron Configuration-partner 5. Uranium’s Electron Configuration-partner

Formative Assessment

Electron Configuration and the Periodic Table

For electron configuration and the s,p,d, and f blocks we will use the following: Lanthanium (La) and Actinium (Ac) are part of the f block. (La - 4f1 and Ac 5f1) Lutetium (Lu) and Lawrencium (Lr) are part of the d block. (Lu - 5d1 and Lr -6d1) There is discrepancies from source to source. However, we will use this way as it supports our diagonal rule and the stability of an atom.

Periodic Table and Electron Configurations

Making It Easier Using Noble Gas Notation, electron configurations can be shortened. Noble gases are in the last column of the periodic table (He-Rn) For any element’s electron configuration, find the noble gas that comes before it. Start with this gas and then finish filling in the subshells. Lithium: [He]2s1 Phosphorus: [Ne]3s23p3

Desk Practice Be P Cd Ce Br Gd Write the electron configuration for the following: Be P Cd Ce Br Gd

Pauli’s Exclusion Principle No two electrons in the same atom can have the same set of four quantum numbers. An orbital can hold at most two electrons, and then only if the electrons have opposite spins. Electron spin has only two possible directions it can spin on it’s axis. ms = +1/2 or ms = -1/2

Writing Electron Configurations with Pauli’s Principle Instead of writing electron configurations using numbers and letters, one must draw an orbital diagram. -You still label the subshells (s, p, f, d) -Write electrons as arrows. Example: Lithium--1s22s1 1s 2s

Practice with Pauli’s Principle According to Pauli’s Principle are the following configurations possible? If no, explain why. 1s 2s 2p 1. 1s 2s 2p 2. 1s 2s 2p 3.

Hund’s Rule Orbitals of equal energy are each occupied by one electron before any orbital is occupied by a second electron. All electrons in singly occupied orbitals must have the same spin state. Ex: Carbon 1s22s22p2 Ex: Oxygen 1s22s22p4 1s 2s 2p 1s 2s 2p

Practice with Hund’s Rule Complete the orbital notation for the ground state of the following atoms: Nitrogen Aluminum Iron

Today’s Purpose Update Objective 1 and 2- Where do you stand? Purple Learning Objective Sheet. Update Objective 1 and 2- Where do you stand? Plan of Action – Learning Opportunities I can write electron configurations using orbital notation, electron configuration notation, and noble gas notation.

TEST on __________!! Electron Arrangement #1 – 25pts See Green Learning Objectives Sheet Atoms: Building Blocks of Matter #2 – 15pts Calculations and Measurement #3 – 10 pts

Electron Configuration Practice Sheets Unit Packet Practice!

Formative Assessment

Today’s Purpose I can write electron configurations using orbital notation, electron configuration notation, and noble gas notation. I can represent the atomic model and atomic structure using quantum numbers.

TEST on _______!! Electron Arrangement #1 – 25pts See Green Learning Objectives Sheet Atoms: Building Blocks of Matter #2 – 15pts Calculations and Measurement #3 – 10 pts

Check for Understanding Complete individually, turn over when finished. Write the electron configurations AND orbital notation for the following elements using the diagonal rule for order of filling. Sulfur (atomic number 16)   Silver (atomic number 47) Europium (atomic number 63)

Atomic Orbitals (Subshells) Atomic Orbital: The most likely place one will find an electron. S orbitals: Spherical in shape. Single Pockets. Two electrons are associated with an s orbital. P orbitals: Dumbbell shape. Groups of three. Six electrons fill the p orbitals.

Atomic Orbitals D orbitals: Clover leaf in shape. Groups of five. Ten electrons fill the d orbitals. F orbitals: Double clover leaf. Groups of seven. 14 electrons fill the f orbitals.

Quantum Numbers Specify the properties of atomic orbitals and the properties of electrons in orbitals. Increase in energy as adding orbitals.

1. Principle Quantum Number Symbol – “n” Indicates the main energy level occupied by the electrons. “n” (electron energy) increases as the distance from the nucleus increases n=1 is the lowest, main energy level More than 1 electron can have the same n value (same electron shell) n can be from 1 to ∞

2. Angular Momentum Quantum Number Orbitals of different shapes (Sublevels) Symbol “L” L = 0 to (n-1) Indicates the shape of the orbitals (s, p, d, f) L= 0 (s) L = 1 (p) L = 2 (d) L =3 (f)

3. Magnetic Quantum Number Symbol = “m” m = -L to +L Indicates orientation of an orbital around the nucleus s (spherical) – 1 possible orientation m= 0 p (lobes – x, y, z) – 3possible orientation m = -1, 0, 1 d – 5 different orientations m = -2, -1, 0, 1, 2 f – 7 different orientations m= -3, -2, -1, 0, 1, 2, 3

4. Spin Quantum Numbers Only has 2 possible values (+ ½ and - ½ ) Indicate the two fundamental spin states of an electron in an orbital. (spin up, first) 1s2 ______ 2p4 Principle Number Shape Number of electrons in shape

TEST … Tomorrow!! Electron Arrangement #1 – 25pts See Green Learning Objectives Sheet Atoms: Building Blocks of Matter #2 – 15pts Calculations and Measurement #3 – 10 pts

Practice/Review Time Unit Packet Practice