1 / 10

Summary of Electron Configurations and Excited States

This summary explains electron configurations in the ground state and the excited state. It also discusses the stability of different energy levels and valence shells. Examples are given to illustrate these concepts.

loridrake
Download Presentation

Summary of Electron Configurations and Excited States

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. SUMMERY (SUMMARY) OF ELECTRON CONFIGURATIONS THE GROUND STATE CONFIGURATION: 1) Given on periodic table. 2) Inner shells are full ( except transition metals, where the last two shells may be incomplete). 3) Most stable, lowest energy configuration. 4) Lower shell numbers are closest to the nucleus and are lowest in energy level. 5) Electrons must exist in shells, also termed energy levels and principle quantum number. 6) The outer shell is the valence shell and is chemically reactive, inner shells are kernel electrons and are chemically inactive. THERE ARE TWO ELECTRONS IN SHELL N=1 ( lowest energy level in Na) 11Na 2-8-1 THERE IS ONE ELECTRON IN SHELL N=3 VALENCE SHELL( highest energy level here) 2-8-1 THERE ARE EIGHT ELECTRONS IN SHELL N=2

  2. 25Mn 2-8-13-2 THERE ARE TWO ELECTRON IN SHELL N=4VALENCE SHELL THERE ARE TWO ELECTRONS IN SHELL N=1 2-8-13-2 THERE ARE EIGHT ELECTRONS IN SHELL N=2 THERE ARE 13 ELECTRONS IN SHELL N=3, TRANSITION METALS (GROUPS 3-12) FREQUENTLY HAVE THE OUTER TWO SHELLS INCOMPLETE. THIS BACKGROUND IS CORN-Y

  3. THE EXCITED STATE CONFIGURATION: 1) Same number of electrons as ground state, different configuration. 2) An electron is promoted from an inner shell (lower energy) to an outer shell (higher energy). 3) An inner shell that is full in the ground state will be incomplete in the excited state. 4) The excited state is temporary and is imediatley followed by fallback. 11Na 2-8-1 2-8-1 GROUND STATE 2-7-2 EXCITED STATE THIS INNER SHELL IS NOT FULL (SHOULD HAVE 8 ELECTRONS) WHICH IS INDICATIVE OF AN EXCITED STATE. 1-8-2 EXCITED STATE

  4. 11Na 2-8-1 EXCITATION e- ENERGY e- e- e- n=3 e- e- e- e- e- n=2 e- e- nuc n=1

  5. 11Na 2-7-2 EXCITED STATE, THE ELECTRON IS IN A HIGHER ENERGY LEVEL THAN ITS GROUD STATE POSITION. e- e- e- e- e- n=3 e- e- e- ELECTRON HOLE, THE VACATED FORMER POSITION OF THE ELECTRON, THE n=2 SHELL IS NO LONGER COMPLETE. e- n=2 e- e- nuc n=1

  6. 11Na 2-7-2 DURING FALLBACK ENERGY IS RELEASED AS LIGHT e- DURING FALLBACK ENERGY IS RELEASED AS LIGHT FALLBACK e- e- e- n=3 e- e- e- e- e- DURING FALLBACK THE ELECTRON BECOMES MORE STABLE AS IT RELEASES ITS ENERGY, GOES BACK TO GROUND STATE. n=2 e- e- nuc n=1

  7. 11Na 2-8-1 e- e- e- e- e- e- e- n=3 e- e- n=2 e- e- nuc n=1

  8. INCREASING ENERGY

  9. U DO IT NOW! For the following configuration: 2-8-18-6 a) Identify the element. b) Propose an excited state. c) How many electrons are in the valence shell? Simply add the electrons, which equal protons in a neutral atom, the atomic number. 2-8-18-6: 2+8+18+6 = 34 electrons indicates an atomic number of 34, which is Se Write a configuration with the same number of electrons as the ground state , but with a different configuration. 2-8-18-6(ground): 2-8-17-7 (excited) ♫NOTE – electrons furthest from the nucleus are most likely to be excited (promoted). 2-8-18-6, 6 valence electrons (and 2+8+18 = 26 kernel)

More Related