Electrons ATOMIC ORBITALS Atomic Orbital region of space

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 1 s (1 orbital) n=2 2 2 s (1 orbital), 2 p (3 orbitals) n=3 3 3 s (1 orbital), 3 p (3 orbitals), 3 d (5 orbitals) n=4 4 4 s (1 orbital), 4 p (3 orbitals), 4 d (5 orbitals), 4 f (7 orbitals)

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

Energy Levels s Sublevels n=1 n=2 s p p d n=3 Nucleus s 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 Hund’s Rule Within a sublevel, place one e- per orbital before pairing them. “Empty Bus Seat Rule” WRONG RIGHT

B. Notation Orbital Diagram O 8 e¢ 1 s 2 s Electron Configuration 2 2 4 1 s 2 s 2 p 2 p

B. Notation Longhand Configuration S 16 e 1 s 2 2 p 6 3 s 2 3 p 4 Core Electrons ¢ Valence Electrons Shorthand Configuration S 16 e- [Ne] 3 s 2 3 p 4

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

C. Periodic Patterns Period # 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.

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

C. Periodic Patterns 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.

C. Periodic Patterns Example - Germanium [Ar] 2 4 s 10 3 d 2 4 p

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

Paramagnetic unpaired electrons 2 p Diamagnetic all electrons paired 2 p 7. 8

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 energy level Full sublevel (s, p, d, f) ¢ Half-filled sublevel ¢

D. Stability Electron Configuration Exceptions l l Copper EXPECT: [Ar] 4 s 2 3 d 9 ACTUALLY: [Ar] 4 s 1 3 d 10 Copper gains stability with a full d-sublevel.

D. Stability Electron Configuration Exceptions l Chromium EXPECT: ACTUALLY: l [Ar] 4 s 2 3 d 4 [Ar] 4 s 1 3 d 5 Chromium gains stability with a half-filled dsublevel.

D. Stability Ion Formation Atoms gain or lose electrons to become more stable. Isoelectronic with the Noble Gases.

D. Stability Ion Electron Configuration Write the e- config for the closest Noble Gas EX: Oxygen ion O 2 - Ne O 2 - 10 e- [He] 2 s 2 2 p 6 The oxygen ion and Neon atom are isoelectric. The atom and ion have the same electron configuration.