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Chapter 4: Arrangement of electrons in atoms. Unit 2 – Electrons and Periodic Behavior Cartoon courtesy of NearingZero.net. Cartoon courtesy of NearingZero.net. 4-1 Properties of Light. Electromagnetic radiation- is a form of energy that exhibits wavelike behavior as it travel through space.
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Chapter 4: Arrangement of electrons in atoms Unit 2 – Electrons and Periodic BehaviorCartoon courtesy of NearingZero.net Cartoon courtesy of NearingZero.net
4-1 Properties of Light • Electromagnetic radiation-is a form of energy that exhibits wavelike behavior as it travel through space. • Examples x-rays, UV, infrared light, microwaves, radio waves • Electromagnetic spectrum all electromagnetic radiation, arranged according to increasing wavelength.
Spectroscopic analysis of the visible spectrum…produces all of the colors in a continuous spectrum • Continuous spectrum- spectrum in which all wavelengths within a given range are included.
Speed of Light • C = v • C= speed of light • 3.0 x 1010 cm/s • 3.0 x 108 m/s • = wavelength (m) • v= frequency (Hz) Crest Trough
Photoelectric effect- is the emission of e- by certain metals when light shines on them
E= h v • E= energy • h= Planck’s constant (6.626x10-34 J.S) • v= frequency • Quantum is a finite quantity of energy that can be gained or lost by an atom. • 1 quantum = 1 photon
Ground state is the state of lowest energy (stable) • Excited state has higher potential energy. Emits light. • Example Neon lights
Wave-Particle Duality • JJ Thomson won the Nobel prize for describing the electron as a particle. • His son, George Thomson won the Nobel prize for describing the wave-like nature of the electron.
4-2 The Quantum Model of the Atom • Quantum Numbers • Each electron in an atom has a unique set of 4 quantum numbers which describe it. • Principal quantum number • Angular momentum (orbital) quantum number • Magnetic quantum number • Spin quantum number
Principal Quantum Number • Generally symbolized by n, it denotes the shell (energy level/shell) in which the electron is located. n=1 n=2 n=3
Angular Momentum Quantum Number • The angular momentum quantum number, generally symbolized by l, denotes the orbital (subshell) in which the electron is located (s,p,d,f). l =0 s l =2 d l =1 p
Magnetic Quantum Number • The magnetic quantum number, generally symbolized by m, denotes the orientation of the electron’s orbital with respect to the three axes in space (x,y,z). Have to split up p, d, f orbitals.
Spin Quantum Number • Spin quantum number denotes the behavior (direction of spin) of an electron within a magnetic field. • Possibilities for electron spin: +1/2 or -1/2
4-3 Electron Configurations • Electron configuration is the arrangement of electrons in an atom. • Aufbau Principle states an electron occupies the lowest-energy orbital that can receive it.
Pauli Exclusion Principle No 2 electrons in the same atom can have the same 4 quantum #’s
Hund’s Rule • States that orbital of equal energy are each occupied by 1 electron before any orbital is occupied by a 2nd electron. Fill in all the up arrows first.
A notation in which only the valence shell electrons of the atom are represented. Lewis-Dot Notation
Orbital Notation x y z x y z x y z
Noble Gas Notation • Is a shorthand configuration. Use the noble gas before the element and then continue with the electron-configuration notation. • Li= (He)2s1 • Al= (Ne)3s23p1
Work Cited • “Aufbau principle chart and electron-configuration of O”. Drawings. Aug. 7, 2006. http://people.uis.edu/gtram1/organic/introduction/intro.htm • “Oxygen Lewis Dot”. Drawing. Aug. 7, 2006. http://edweb.tusd.k12.az.us/Secrist/teachers/rjones/what_we_have_accomplished_in_the.htm • “Wavelength diagram and prism diagram” Pictures. Aug. 7, 2006. http://eqseis.geosc.psu.edu/~cammon/HTML/Classes/PhysicalGeology/Notes/Chapter02/P03.html • “Orbital Notations”. Drawings. Aug, 7, 2006. http://www.chemistry.ohio-state.edu/~grandinetti/teaching/Chem121/lectures/periodic%20trends/ionization_energy.html • “xyz axis”. Drawing. Aug. 7, 2006. http://wine1.sb.fsu.edu/chm1045/notes/Struct/QMech/Struct05.htm • “Electron shape chart”. Chart. Aug. 7, 2006. http://wine1.sb.fsu.edu/chm1045/notes/Struct/QMech/Struct05.htm • “spd orbitals”. Drawing. Aug. 7, 2006. http://chemed.chem.purdue.edu/genchem/topicreview/bp/ch6/quantum.html
“Atom”. Drawing. Aug. 7, 2006. http://bioweb.wku.edu/courses/Biol115/Wyatt/Exam1/Quiz1/quiz1.htm • “Periodic Table”. Drawing. Aug. 7, 2006.http://www.epcc.edu/faculty/victors/elconfig.htm • “Route 66 sign”. Photo. Aug. 7, 2006. http://www.lightgod.com/led.asp?catid=865 • “Neon Sign”. Photo. Aug. 7, 2006. http://www.neon-signage.com/ • “Photo electric effect”. Picture. Aug. 7, 2006. http://www.pa.msu.edu/courses/1997spring/PHY232/lectures/quantum/photoelectric.html • “S,P,D,F blocks on periodic table”. Drawing. Aug. 8, 2006. http://wine1.sb.fsu.edu/chm1045/notes/Struct/EPeriod/Struct09.htm • “Wolfgang Pauli”. Photo. Aug. 8, 2006. http://www.homeoint.org/dynamis/synchro.htm
“Na and Cl lewis dot struture”. Drawing. Aug 8, 2006. http://www.d94.org/science/carrow/chemistry/interactions/calendar/notes/lewis.htm • Information. Aug 6, 2006. http://www.sciencegeek.net/Chemistry/Powerpoint/Unit2/Unit2_files/frame.htm • Holt, Rinehart and Winston. Modern Chemistry. Harcourt Brace & Company. 1999.