Quantum Theory Schroedinger’s Cat Place a cat in a box Also place a radioactive isotope and a vial of poison The isotope decays once per hour If the particle triggers a Geiger counter, the cat dies If the Geiger counter is not triggered, the cat lives Seal the box and wait an hour What happened to the cat?

Electromagnetic Spectrum The speed of light© is 3.00 x 108 m/s

Photoelectric Effect The emission of _________ from a metal when ______________ on the metal Light had to be a certain ______________ ____for electrons to be emitted Wave theory of light said that _____________ of light should have worked This led to the concept of light as a ___________

Light as a particle Max Planck (1900) Hot objects emit light and other forms of electromagnetic radiation, but not continuously, as expected Instead, it is emitted in small, specific amounts called quanta. E=hv H=6.626 x 10 -34 J*s This number is called Planck’s constant

Dual Nature of Light Albert Einstein (1905) Light behaves as a ________ when it travels through space Light behaves as a _________ when interacting with matter Even though it isn’t quite right to do so, you can think of light as a __________________ that travels as a wave A _________ is a massless bundle of light E photon=hv Some metals hold electrons more tightly than others and require ____________________ to move electrons

Emission Spectra Ground State ___________ energy state of an electron Excited State ___________ energy state Energy is absorbed to move from ___________ ___________ states and is released as ___________ ___________ when returning to the ground state ___________ ___________ of light are emitted for any given element ___________ spectrum- ___________ range of em light(rainbow) (Bright) Line emission spectrum-Only ___________ ___________ of light are seen

The Bohr Model Niels Bohr (1913) Allowed for electrons to have ___________ Electrons have ___________ energies Lower energy- ___________ to nucleus Higher energy- ___________ from nucleus Electrons can ___________ energy to raise to the next energy level and ___________ the same energy when falling to the ground state This model works well for ___________ but not for other elements

Electrons as Waves Louis de Broglie (1924) Suggested that electrons could be considered as ___________ confined to the space around a nucleus ___________ - bending of light around edges Wave Interference- when waves ___________

Quantum Theory Werner Heisenberg (1927) The Uncertainty Principle One cannot simultaneously know the ___________ and ___________ of an electron

Quantum Theory Erwin Schroedinger (1926) Wave Equation- The quantization of an electron’s energies is an outcome Quantum Theory-mathematically describes wave properties of ___________ and other ___________ ___________

Atomic Orbitals and Quantum Numbers Quantum Numbers- properties of ___________ ___________ and properties of ___________ in orbitals Like the address of an electron or a seat in a stadium or theater

Principal Quantum Number 1,2,3 K,L,M This would be like the section on a ticket for a stadium seat

Angular Momentum Quantum Number ___________ of an orbital 0,1,2,3 s,p,d,f Like the row in a stadium or theater

Magnetic Quantum Number ___________ of an orbital around the nucleus +1 to -1 Like finding your seat in a stadium or theater

Spin Quantum Number Ms Fundamental ___________ of an electron +1/2 or -1/2 A single orbital can hold up to a maximum of ___________ of ___________ spin This would be which direction you are facing in a theater or stadium seat

Some Quantum Theory Rules Pauli Exclusion Principle- No two electrons have the same set of ______________________ . Or An orbital within a sublevel can contain up to ___________ of opposite spin Hund’s Rule- Each orbital within a ___________ receives an electron of ___________ spin before any can receive an electron of ___________ spin