Presentation on theme: "Isotope Formulae, Electron Configurations & Orbital Diagrams"— Presentation transcript:
1 Isotope Formulae, Electron Configurations & Orbital Diagrams
2 Isotope Formulae Provide element’s symbol Mass number Atomic number mass# = #p+ + #nwritten as a superscript to the leftAtomic numberatomic# = #p+ or #e-written as a subscript to the left
3 X C C Isotope Formulae Mass# Atomic# 12 6 13 6 Carbon has two naturally occurring isotopes:carbon-12 and carbon-13C126C136
4 Isotope FormulaeGive the isotope formula for each of thefollowing:H311. Hydrogen with 2 neutronsF1892. Fluorine with 9 neutronsU235923. Uranium with 143 neutrons
5 Valence Electron(s)The electron(s) farthest from the nucleus or in the outermost energy level.
6 Aufbau Principle Comes from German word meaning “to build” Electrons will occupy lower energy orbitals first
7 Pauli Exclusion Principle An atomic orbital can hold at most two electrons.If an atomic orbital holds two electrons, they must have opposite spins.
8 Hund’s RuleWhen filling atomic orbitals of equal energy, place electrons with parallel spins in the orbitals first. Then, place the oppositely spinning electrons in to the orbitals.
9 Electron Configurations Also describe where electrons live within an atomIt’s like a translation of quantum numbers.They give the energy level, atomic orbital, and number of electrons residing in the orbital and energy level.
10 Electron Configurations Energy levelMay be any positive integerJust like the principal quantum number
11 Electron Configurations Atomic Orbital or SublevelRepresented by letters: s, p, d, fTranslates azimuthal number and magnetic numbers is the same as l = 0p is the same as l = 1d is the same as l = 2f is the same as l = 3
12 Electron Configurations Number of Electronsin either an atomic orbital or a sublevelmax of 2 in the s sublevelmax of 6 in the p sublevelmax of 10 in the d sublevelmax of 14 in the f sublevel
13 Electron Configurations Use the periodic table to guide you in writing electron configurations.Find the link between 2,6,10, and 14 and the periodic table.
14 Electron Configurations Hydrogenenergy level1s1# of electronssublevel/orbital
15 Electron Configurations Write the e- configurations of the next 9 elements (through Ne).He…1s2Li…1s22s1Look at the sumof the superscripts…Be…1s22s2B…1s22s22p1
16 Electron Configurations 1s22s22p2N…1s22s22p3O…1s22s22p4F…1s22s22p5Ne…1s22s22p6
17 Electron Configurations Shorthand configurations are written by assuming that you can let the symbol of the noble gas preceding the valence electrons represent the e- configuration to that point.
18 Electron Configurations …shorthand He…1s2Li…[He]2s1Be…[He]2s2B…[He]2s22p1C…[He]2s22p2
19 Electron Configurations …shorthand [He]2s22p3O…[He] 2s22p4F…[He] 2s22p5Ne…[He] 2s22p6
20 Electron Configurations …shorthand Na…[Ne]3s1Si…[Ne] 3s23p2Cl…[Ne] 3s23p5Ar…[Ne] 3s23p6
21 Electron Configurations …shorthand Ca…[Ar]4s2Sc…[Ar] 4s23d1Mn…[Ar] 4s23d5Se…[Ar] 4s23d104p4
22 Electron Configurations …shorthand [Kr] 5s24d105p5La…[Xe] 6s25d1Ce…[Xe] 6s25d14f1Hg…[Xe] 6s24f145d10
24 Orbital DiagramsShow the electron configuration while illustrating the Aufbau Principle, Pauli Exclusion Principle, and Hund’s RulePlace energy on the y-axisUse lines to represent orbitalsUse up and down arrows to indicate spin
25 Orbital Diagrams (template) 3px3py3pz3sE2px2py2pz2s1s