Light: waves or particles?
Light: waves or particles? • • • • • •
• Light from hot objects was not emitted continuously, like you would expect if light was moving in a transverse wave
• Energy is emitted from hot objects in small packets called quanta • A quantum of energy specific amount of energy • Figured out how to calculate the amount of energy being carried in a quanta of energy
• • • •
• • ·
•
However much energy is carried by light when it is behaving like a wave …. A photon of that same color carries the same amount of energy
Bohr model http://www.videopediaw orld.com/video/35098/Ni els-Bohrs-Atomic-Model
http://science.sbcc .edu/physics/flash/ siliconsolarcell/bo hratom.swf
•
•
• • • • Red light of frequency of 4.37 x 1014 Hz is required to excite a certain electron. What energy did the electron gain from the light?
• Ephoton = h v
SO FAR………… Photoelectric effect- light of certain frequency(AKA: certain amount of energy) to dislodge electrons Max Plank- energy released in “packets” not streams or waves Einstein- wave-particle duality of light Bohr Model of atom • light of certain wavelength must be absorbed for electrons to jump to certain energy levels- a quanta of energy must be absorbed • Electrons return to their ground state and give off that same amount energy in the form of a photon- certain colors • Electrons in distinct energy levels
Atomic Spectrum • Each element has a unique brightline emission spectrum- Atomic
Spectrum • this comes from the electrons emitting different colors of light
Louis De Broglie -1923 • Expanded on Einstein’s research • Electrons have wave- particle duality • AKA: electrons can behave like a wave and like a particle http://ed.ted.com/lessons/particles-andwaves-the-central-mystery-of-quantummechanics-chad-orzel
Erwin Schrodinger-1926 • Quantum mechanical model • This model portrays a nucleus surrounded by an electron cloud. • Where the cloud is most dense, the probability of finding the electron is greatest- cloud is less dense, electron less likely to be
Werner Heisenberg- 1928 Uncertainty Principle- it is impossible to determine simultaneously both the position and velocity of an electron. http://ed.ted.com/lessons/what-is-theheisenberg-uncertainty-principle-chadorzel
Basic Arrangement of Electrons in Atoms Main Energy Levels SUBLEVELS ORBITALS
• Light from hot objects was not emitted continuously, like you would expect if light was moving in a transverse wave
• Energy is emitted from hot objects in small packets called quanta • A quantum of energy specific amount of energy • Figured out how to calculate the amount of energy being carried in a quanta of energy
• • • •
• • ·
•
However much energy is carried by light when it is behaving like a wave …. A photon of that same color carries the same amount of energy
Bohr model http://www.videopediaw orld.com/video/35098/Ni els-Bohrs-Atomic-Model
http://science.sbcc .edu/physics/flash/ siliconsolarcell/bo hratom.swf
•
•
• • • • Red light of frequency of 4.37 x 1014 Hz is required to excite a certain electron. What energy did the electron gain from the light?
• Ephoton = h v
SO FAR………… Photoelectric effect- light of certain frequency(AKA: certain amount of energy) to dislodge electrons Max Plank- energy released in “packets” not streams or waves Einstein- wave-particle duality of light Bohr Model of atom • light of certain wavelength must be absorbed for electrons to jump to certain energy levels- a quanta of energy must be absorbed • Electrons return to their ground state and give off that same amount energy in the form of a photon- certain colors • Electrons in distinct energy levels
Atomic Spectrum • Each element has a unique brightline emission spectrum- Atomic
Spectrum • this comes from the electrons emitting different colors of light
Louis De Broglie -1923 • Expanded on Einstein’s research • Electrons have wave- particle duality • AKA: electrons can behave like a wave and like a particle http://ed.ted.com/lessons/particles-andwaves-the-central-mystery-of-quantummechanics-chad-orzel
Erwin Schrodinger-1926 • Quantum mechanical model • This model portrays a nucleus surrounded by an electron cloud. • Where the cloud is most dense, the probability of finding the electron is greatest- cloud is less dense, electron less likely to be
Werner Heisenberg- 1928 Uncertainty Principle- it is impossible to determine simultaneously both the position and velocity of an electron. http://ed.ted.com/lessons/what-is-theheisenberg-uncertainty-principle-chadorzel
Basic Arrangement of Electrons in Atoms Main Energy Levels SUBLEVELS ORBITALS
