A New Approach to the Atom

Objectives: • 1. Describe the atomic orbitals in terms of their shape, size, and energy.

Key Terms: • quantum-mechanical model, electron density, orbital principle energy level, sublevel

Probability & Orbitals

• • Schrodinger stated that electron orbitals can more correctly referred to as electron clouds. An orbital is the region around the nucleus where an electron is likely to be found. • Within an orbital it is more likely to find the electron nearer to the nucleus than toward its boundary There are 4 basic orbital types: s,p,d,& f orbitals. • Each orbital can hold a maximum of 2 electrons each with opposite spin

s orbital

• • Spherical in shape 1 st orbital in any energy level and only orbital located at n=1

p orbital

• • • The p orbital is dumbbell shaped The p-orbitals begins in the 2 nd energy level The are 3 orbitals in the p-orbital system • • The orbitals extend out on the x, y, & z axis (p x ,p y ,p z ) The system can hold a maximum of 6 electrons

d-orbital

• • • The d orbital is dumbbell and donut shaped The d-orbital begins in the 3 rd energy level The are 5 orbitals in the d-orbital system • The orbitals extend out at angles to the x, y, & z axis • The system can hold a maximum of 10 electrons • Considered a suborbital system and is inserted after 4s

f-orbital

• • • The f-orbitals begins in the 4 th energy level The are 7 orbitals in the d-orbital system • • The orbitals extend out at angles to the x, y, & z axis The system can hold a maximum of 14 electrons Considered a suborbital system to the d-block and is inserted after 6s

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Orbital Summary for the Principle Energy Levels

The number of the energy level is equal to the number of orbital sublevels n=1 1 sublevel 1s (2 electrons) n=2 2 sublevels 2s, 2p (8 electrons) n=3 3 sublevels 3s, 3p, 3d (18 electrons) n=4 4 sublevels 4s, 4p, 4d, 4f (32 electrons) • • • • Number of electrons possible for each orbital sublevel: s = 1 (2 electrons) p = 3 (6 electrons) d = 5 (10 electrons) f = 7 (14 electrons)