Aim: How are electrons arranged in an atom? Do Now: Please take four different colored pencils or highlighters and a Periodic Table.

Heisenberg Uncertainty Principal Just remember… It is impossible to know the precise location and velocity of an electron.

The Wave-Mechanical Model: Electrons exist in a cloud.

Dr. Niel Bohr’s Model of the Atom Bohr stated that electrons move in principle energy levels or shells around the nucleus. n=1 n=2 n=3 n=4 n=5 n=6 n=7

1. Principle Energy Levels Principle Energy Level (“shell”): The region where there is the highest probability of locating an electron Principle Quantum Number (n): The number given to the shell or principle energy level. Ex: n=2 refers to the 2nd shell/energy level. On your periodic table, label the Principle Energy Levels (n).

On your periodic table, label the Principle Energy Levels (n).

On your periodic table, label the sublevels. All principal energy levels have one or more sublevels. Sublevels are labeled s,p,d, and f. s<p<d<f describes the order of increasing energy. The “n” (number of Principle Energy Levels) tells how many sublevels there are. On your periodic table, label the sublevels.

On your periodic table, label the sublevels (s, p, d, and f) and color code.

Aim: How are electrons arranged in an atom? Period 6 Do Now: Complete the expanded electron configurations for each of the following atoms: Arsenic Nickel Rubidium

Principal Energy Level (n) Maximum Number of Electrons 3. Orbitals Each orbital can hold 2 electrons. Each sublevel has one or more orbitals. Sublevel s has 1 orbital. Sublevel p has 3 orbitals. Sublevel d has 5 orbitals. Sublevel f has 7 orbitals. (Each sublevel has two more orbitals than the previous one. Remember the first four odd #s.) Principal Energy Level (n) Type(s) of Sublevel Number of Orbitals Maximum Number of Electrons 1 s 2 p 3 6 d 5 10 4 f 7 14

Principal Energy Level (n) Maximum Number of Electrons Each orbital can hold a maximum of 2 electrons. Each sublevel has one or more orbitals. Principal Energy Level (n) Type(s) of Sublevel Number of Orbitals Maximum Number of Electrons 1 s 2 p 3 6 d 5 10 4 f 7 14

On your periodic table, fill in the electron numbers in each subshell.

Electrons always fill the orbitals always fill in a very specific pattern. You don’t have to memorize these if you understand how the periodic table works.

Electrons always fill the orbitals always fill in a very specific pattern. You don’t have to memorize these if you understand how the periodic table works.

17Cl - _____________________________ Extended Electron Configuration: Shows how many electrons are in each P.E.L. and sublevel. Give the extended electron configuration for the following elements: 17Cl - _____________________________ 9F - _______________________________ 15P - ______________________________ You don’t have to memorize these if you understand how the periodic table works.

Noble Gas Configuration: Shows how many electrons are in each P.E.L. and sublevel in an abbreviated format. Give the Nobal Gas configuration for the following elements: 17Cl - _____________________________ 9F - _______________________________ 15P - ______________________________ You don’t have to memorize these if you understand how the periodic table works.

Aim: How are electrons arranged in an atom? Period 3 Do Now: Complete the expanded electron configurations AND the noble gas configurations for each of the following atoms: Arsenic Nickel Rubidium

As 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3 + 4d 5s 4p 3d 4s s p 1 3p 2 d 3 3s 1 2 p 1 3p 1 2 3 4 5 6 2 d 3 3s 1 2 3 4 5 6 7 8 9 10 4 5 2p 6 7 2s As f 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p3 1s +

Ni 1s2 2s2 2p6 3s2 3p6 4s2 3d8 + 4d 5s 4p 3d 4s s p 1 3p 2 d 3 3s 4 5 1 2 p 1 3p 1 2 3 4 5 6 2 d 3 3s 1 2 3 4 5 6 7 8 9 10 4 5 2p 6 7 2s Ni f 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1s2 2s2 2p6 3s2 3p6 4s2 3d8 1s +

Rb 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 + 4d 5s 4p 3d 4s s p 1 3p 2 d 1 2 p 1 3p 1 2 3 4 5 6 2 d 3 3s 1 2 3 4 5 6 7 8 9 10 4 5 2p 6 7 2s Rb f 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p6 5s1 1s +

Hund’s Rule 1s22s22p2 2-4 Carbon Which neutral element does this configuration represent? Carbon

Pauli Exclusion Principle 1s22s22p2 2-4 An orbital pair of electrons must have opposite spins. The notation for an electron pair is...

17Cl - _____________________________ Orbital Notation: Uses up and down arrows to show the electron pairs occupying each orbital. Give the orbital notation for the following elements: 17Cl - _____________________________ 9F - _______________________________ 15P - ______________________________ You don’t have to memorize these if you understand how the periodic table works. Remember: s has 1 orbital & p has 3 orbitals. __ __ __ __ __ __ __ __ __ 1s 2s 2p 3s 3p

Practice Writing Bohr Electron Configuration (from reference table) Give the Bohr electron configuration for the following elements: 17Cl - _____________________________ 9F - _______________________________ 15P - ______________________________ You don’t have to memorize these if you understand how the periodic table works.

4d 5s 4p 3d 4s s 1 2 p 1 3p 1 2 3 4 5 6 2 d 3 3s 1 2 3 4 5 6 7 8 9 10 4 5 2p 6 7 2s Cl f 1 2 3 4 5 6 7 8 9 10 11 12 13 14 1s2 2s2 2p6 3s2 3p5 1s +