Textbook Notes (280,000)

US (110,000)

Berkeley (2,000)

CHEM (100)

CHEM 1A (80)

Arnold Yuan (20)

Chapter 7.4

This

**preview**shows half of the first page. to view the full**2 pages of the document.**Lecture 6: Electron Clouds

PRE-READING NOTES

7.4 pg. 294-295

7.4 The Wave Nature of Matter: The de Broglie Wavelength, the Uncertainty Principle,

and Indeterminacy

Louis de Broglie 1924, 1927 – electrons have wavelike nature

2 slit experiment – see an interference pattern instead of 2 bright spots

interference pattern caused by electrons interfering with themselves electrons

individually have a wavelike nature

de Broglie wavelength- wavelength of electron related to KE

de Broglie relation:

λ=h

mv

h is Planck’s constant

if you place a laser right after the 2 slits no more interference pattern, and flash always

originates from either one slit or the other

cannot simultaneously observe both the wave nature and particle nature of an electron

complementary properties – exclude one another

velocity – wave-like nature

position – particle nature

cannot simultaneously measure position and velocity of electron

Heisenberg’s uncertainty principle:

Δx ×m Δv ≥ h

4π

- more accurately you know the position of an electron (the smaller Δx), the less

accurately you can know its velocity (the bigger Δv) and vice versa

Newton’s laws deterministic – present determines the future

Probability distribution maps – stats to show where electron is likely to be found

Indeterminacy – future path is indeterminate

7.5-7.6 pg. 297-303

7.5 Quantum Mechanics and the Atom

velocity directly related to energy

energy and position therefore complementary

orbital – describes electron position – probability distribution map

= Ηψ Εψ

H is Hamiltonian operator – operations that represent total energy of electron within the

atom

E – energy of electron

– wave function – describes wavelike nature of the electron – mathematical descriptionΨ

of the amplitude of the electron wave

Ψ2 – orbital – position probability distribution map

Solution to equation is a bunch of possible wave functions, which correspond to orbitals

Quantum numbers:

###### You're Reading a Preview

Unlock to view full version