Bohr Models – Selected Ans Sodium [11] p + s = 11 e - s = 11 1 st ring = 2 e - s 2 nd ring = 8 e - s 3 rd ring = 1 e - s Carbon [6] p + s = 6 e - s = 6.

Bohr Models – Selected Ans

Unit 2 – Lecture 4

Background Information

Describing Orbitalse-s exist in shells surrounding the nucleus

Lewis dot structures – show valence shell of e-s onlycan be used to show bonding

Describing Orbitals – cont’dBohr Models – show basically same info but

includes also the other levels used to figure out valence e-

further knowledge has shown that e-s actually move in a cloud, taking up more than just ringsmodel to the right is about

70 years out of date!!

Quantum Numbers

Quantum Numbers – cont’d

***the 4***the 4thth level “s” level “s”

fills fills before before the 3the 3rdrd

“d” “d” level!!!!!level!!!!!

Quantum #s ExamplesHydrogen –

# of e-s = [recall: atoms are neutral] = 1e-s determine shellswill only fill part of the first “s” orbitalwe note this as “ 1s1 ”

meaning 1st s orbital w/ 1 e-

Quantum #s ExamplesPhosphorous –

# of e-s = [recall: atoms are neutral] = 15e-s determine shells15 e-s; fill from bottom upnotation:

1s2 2s2 2p6 3s2 3p3

Quantum #s ExamplesManganese –

# of e-s = [recall: atoms are neutral] = 25e-s determine shells25 e-s; fill from bottom upnotation:

1s2 2s2 2p6 3s2 3p6 4s2 3d5

Quantum #s & Periodic TablePeriod Indicates Quantum Numbers!!!

Just count across the periods…