Arrangement of e-

• e- are arranged in ENERGY LEVELS

• There are 7 energy levels• Level 1 is closest to the nucleus and has

the lowest energy• Level 7 is farthest from the nucleus and has the highest energy

Each energy level has sublevels

There are 4 types of sublevel:

S, P, D, and F

Each sublevel has orbitals

Orbitals are locations within the atom where the e- are likely to be found

Each orbital can hold 2 electrons

S sublevel orbitalsS orbitals are Spherical shapes

There is one S orbital1 S x 2 e- = 2 e- can fit in S sublevel

P sublevel orbitals

P orbitals are “peanut” shaped

There are 3 P orbitals, one in each dimension.3 P x 2 e- = 6 e- can fit in P Sublevel

D sublevel orbitals

D orbitals are “double peanut” shaped

There are 5 D orbitals5 D x 2 e- = 10 e- can fit in D sublevel

F sublevel orbitals

F orbitals are “fancy” shaped

There are 7 D orbitals7 D x 2 e- = 14 e- can fit in F sublevel

To Summarize:

7 energy levels4 sublevels ( S, P, D, F)

S orbitals = holds 2 e-P orbitals = holds 6 e-D orbitals = holds 10 e-F orbitals = holds 14 e-

Arrangement of e- in the atom

7 s 7 p 7 d 7 f6 s 6 p 6 d 6 f5 s 5 p 5 d 5 f4 s 4 p 4 d 4 f3 s 3 p 3 d2 s 2 p1 s

Arrangement of e- in the atom (aufbau)

nucleus

Writing electron configurations

____ represents an orbital

represents an e- with “up” spin represents an e- with “down” spin

_____ two e- of opposite spin fill the orbital

What element is this?

1

What element is this?

2

What element is this?

2 1

Electron configuration for Ne

___ ___ ____ ____ ____1s 2s 2p2 2 6

Write the e- configuration of As33

Write the e- configuration of As33

___ ___ ___ ___ ___ ___ ___ ___ ___ 1s2 2s2 2p6 3s2 3p6

___ ___ ___ ___ ___ ___ ___ ___ ___4s2 3d10 4p3

e- will not pair up in p, d or f orbitalsif there is room in the orbital for them to spread out !

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

2 – 8 - 8- 2

What element?

2 2 5

What element?

2 2 6 2 3