Presentation on theme: "Pages 90-99 Electrons deBroglie—proved that particles with mass could have wave-like properties. A stream of e- could behave similar to a wave. He created."— Presentation transcript:
Electrons deBroglie—proved that particles with mass could have wave-like properties. A stream of e- could behave similar to a wave. He created the “wave-particle duality of nature” concept
Quantum mechanics Two types of movement: A) Newtonian Mechanics—describes behavior of objects big enough to see with unaided eye and traveling at ordinary speeds ( cars, planes, space shuttle)
Quantum mechanics B) Quantum Mechanics---describes behavior of objects too small to be seen with the unaided eye and traveling at a velocity near the speed of light (e - )
Electrons Heisenberg Uncertainty Principle—the position of an e- cannot be determined with certainty, because in order to “see” the e- one must strike it with a photon of light and this will change the momentum and the position.
Electrons Momentum---product of mass and velocity
Electrons Electron Cloud Model-(Quantum Model) –The nucleus is positive---due to p + –The nucleus has neutral n o –The mass of atom is in nucleus –The volume around the positive center in which the electrons are most likely located is referred to as the “e - cloud”
Electrons The e - cloud is the area of greatest probability in which the e - are most likely to be found at any given time.
Electrons Erwin Schrodinger-----derived an equation that treated the e- of H atom as a wave. He applied to all atoms.
Electrons Schrodinger’s quantum mechanical model of the atom describes each e- using 4 quantum numbers: “n” ---principal quantum number value of 1-7 indicates the “size of e- cloud”
Electrons “l” ----sublevel of energy value of 0 to n-1 indicates the “shape of the cloud” “m” ----describes cloud orientation in space “s” ---describes the spin of the e- values: clockwise spin +1/2 counterclockwise spin –1/2
Electrons Greatest number of electrons in any energy level may be determined by :2n 2 Quantum level max e- number 12 2 8 3 18 4 32
Electrons Sublevels of energy: “s”---spherical shape only 2e- “ p” ----3 in number ( 2e- each) dumbbell in shape located on 3 axis “d” -----5 in number ( 2e- each) “ f” -----7 in number ( 2e- each )
Electrons Orbital ---space occupied by 2 e- Degenerate orbital---orbital with the same number of electrons and energy 3 p orbitals 5 d orbitals 7 f orbitals
Electrons Pauli Exclusion Principle---no two e - in an atom have the same set of 4 quantum #. E- in the same orbital must have opposite spins Hund’s Rule—no orbital can have 2e- until all orbitals have at least 1 e- Aufbau Principle---e- fill lower energy orbital first ( demo on board)
Two exceptions to the filling rule: Cr----24 Cu -----29
Simplified notation or noble gas notation Use chart to find previous “noble gas” and work the e-configuration from there Demo
Periodic chart divided into : Rows or periods-----( principal quantum #) Groups or families ( vertical columns) Group 1 alkali metals Group 2 alkaline earth metals Group 17 halogens Group 18 noble gas
Electrons Demo: e-configuration p 99 orbital diagrams--- noble gas notation arrow diagram---
Electron Dot Diagram Electrons in the outer most energy level are the e- most often involved in a chemical reaction. Valence e- ---- the e- in outer energy level Lewis Dot diagram: –Write the e-configuration for the element –Write the chemical symbol –Valence e- are placed in the 4 locations around the symbol –pairing them as necessary
Electron dot diagrams Write the Lewis dot diagram for: Carbon Chlorine Nickel Sodium Neon Calcium
Electron Dot Diagram Two exceptions to filling rule are: Copper Chromium
Wave-particle duality of nature Probability Electron cloudquantum mechanics Heisenberg Uncertainty principle Lewis e- dot diagram Momentum Newtonian mechanics Orbitalprincipal quantum number Pauli exclusion principle Sublevel
Work to do!! Page 126 # 12 Page 134 # 17 Page 141 #25,26,28 Page 145---vocab list Page 146-149----# 38,39,44,46,49,52,53,55,59,61,64,78,79,80, 81,82,84,86,87,91,93,101,102,103,104, Princeton review: 3,5,6,7,8,9,10