Electrons

ATOMIC ORBITALS Atomic Orbital: region of space in which there is a high probability of finding an electron. Denoted by letters: s, p, d, and f Each atomic orbital corresponds to a specific shape at a specific energy level. s - spherical p – dumbbell-shaped d – clover leaf-shaped f – more complex

ATOMIC ORBITALS Type of Sublevel Number of Orbitals Number of Electrons s 1 2 p 3 6 d 5 10 f 7 14

ENERGY LEVELS & SUBLEVELS Principle Energy Level Number of Sublevels Type of Sublevel n=1 1 1s (1 orbital) n=2 2 2s (1 orbital), 2p (3 orbitals) n=3 3 3s (1 orbital), 3p (3 orbitals), 3d (5 orbitals) n=4 4 4s (1orbital), 4p (3 orbitals), 4d (5 orbitals), 4f (7 orbitals)

MAXIMUM NUMBER OF ELECTRONS FOR EACH ENERGY LEVEL Energy level (n) Max number of Electrons 1 2 8 3 18 4 32

Energy Levels s Sublevels n = 1 n = 2 s p n = 3 s p d n = 4 f s p d Nucleus s p d n = 4 f s p d

Electron Configuration The most stable arrangement of electrons in sublevels and orbitals.

A. General Rules Aufbau Principle Electrons fill the lowest energy orbitals first. “Lazy Tenant Rule”

A. General Rules Pauli Exclusion Principle Each orbital can hold TWO electrons with opposite spins.

A. General Rules WRONG RIGHT Hund’s Rule Within a sublevel, place one e- per orbital before pairing them. “Empty Bus Seat Rule” WRONG RIGHT

1s2 2s2 2p4 O B. Notation 1s 2s 2p 8e- Orbital Diagram Electron Configuration 1s2 2s2 2p4

S 16e- 1s2 2s2 2p6 3s2 3p4 S 16e- [Ne] 3s2 3p4 B. Notation Longhand Configuration S 16e- 1s2 2s2 2p6 3s2 3p4 Core Electrons Valence Electrons Shorthand Configuration S 16e- [Ne] 3s2 3p4

C. Periodic Patterns s p d (n-1) f (n-2) 1 2 3 4 5 6 7 6 7 © 1998 by Harcourt Brace & Company

C. Periodic Patterns Period # A/B Group # Column within sublevel block energy level (subtract for d & f) A/B Group # total # of valence e- Valence electrons are electrons in the outermost energy level. Determines the chemical and physical properties of an element. Column within sublevel block # of e- in sublevel

Bellwork – 10/4/16 Take a copy of the Magnetic Properties of Metals Lab This will be turned in for a lab grade Begin working on the electron configuration and orbital notation for the elements listed.

1s1 C. Periodic Patterns 1st column of s-block 1st Period s-block Example - Hydrogen 1s1 1st column of s-block 1st Period s-block

C. Periodic Patterns p s d (n-1) f (n-2) Shorthand Configuration Core e-: Go up one row and over to the Noble Gas. Valence e-: On the next row, fill in the # of e- in each sublevel. s d (n-1) f (n-2) p

C. Periodic Patterns Example - Germanium [Ar] 4s2 3d10 4p2

Magnetic Spin Remember Pauli’s Exclusion Principle – electrons fill orbitals with 2 electrons of opposite spins. ms = +½ ms = -½ 7.6

Paramagnetism and Diamagnetism attracted to a magnetic field unpaired electrons Diamagnetism Repelled by a magnetic field Paired elecrons

7.8 Paramagnetic Diamagnetic unpaired electrons all electrons paired

Determining Para/Diamagnetism Substance is placed between electromagnets. If the substance appears heavier, it is attracted in the magnetic field, and is paramagnetic. If the substance appears lighter, it is diamagnetic.

D. Stability Full sublevel (s, p, d, f) Half-filled sublevel Full energy level Full sublevel (s, p, d, f) Half-filled sublevel

D. Stability Electron Configuration Exceptions Copper EXPECT: [Ar] 4s2 3d9 ACTUALLY: [Ar] 4s1 3d10 Copper gains stability with a full d-sublevel.

D. Stability Electron Configuration Exceptions Chromium EXPECT: [Ar] 4s2 3d4 ACTUALLY: [Ar] 4s1 3d5 Chromium gains stability with a half-filled d-sublevel.

D. Stability 1+ 2+ 3+ 4± 3- 2- 1- Ion Formation Atoms gain or lose electrons to become more stable. Isoelectronic with the Noble Gases. 1+ 2+ 3+ 4± 3- 2- 1-

D. Stability O2- 10e- [He] 2s2 2p6 Ion Electron Configuration Write the e- config for the closest Noble Gas EX: Oxygen ion  O2-  Ne The oxygen ion and Neon atom are isoelectric. The atom and ion have the same electron configuration. O2- 10e- [He] 2s2 2p6