1 / 18

Ionization Energies and Group Numbers

Ionization Energies and Group Numbers. What is Ionization?. Consider an atom of Lithium, losing its electrons. The lithium atom has three electrons (1s 2 2s 1 ) and three protons. +. It is electrically neutral 3 e - + 3p + = Li 0. What is Ionization?. Li 0  Li 1+.

diem
Télécharger la présentation

Ionization Energies and Group Numbers

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. Ionization Energies and Group Numbers

  2. What is Ionization? • Consider an atom of Lithium, losing its electrons The lithium atom has three electrons (1s22s1) and three protons + It is electrically neutral 3 e- + 3p+ = Li0

  3. What is Ionization? Li0 Li1+ • When Lithium loses an electron, it becomes positively charged • 2 e- + 3p+ = Li+ +

  4. Ionization Energy • This is fairly easy to do. It takes little energy • It has only 3 protons pulling the electron in. • It is relatively far away from the nucleus • It is being “shielded” by two other electrons. { +++ +

  5. Ionization of Multiple Electrons Li1+ Li2+ • Consider how difficult it would be to ionize the 2nd electron • It will be much more difficult and require more energy to remove this electron +

  6. Ionization of Multiple Electrons • It still has 3 protons pulling the electron in. • It is much closer to the nucleus and so has a stronger pull • It is not being “shielded” by other electrons. { +++ +

  7. Ionization of Multiple Electrons Li2+ Li3+ • The 3rd electron would be just a little more difficult than the 2nd electron +

  8. 2nd electron is much harder 1rst electron is not hard 3rd electron is little different Ionization of Multiple Electrons A graph of the ionization energy of Lithium vs. electron number would look like: IE (kJ/mol) 0 1rst 2nd 3rd Electron Number

  9. Ionization of Multiple Electrons The large “jump” in energy needed between removing the 1st and 2nd electrons comes from the change in levels of the electrons. IE (kJ/mol) 0 1rst 2nd 3rd Electron Number

  10. Hard Easy Ionization of Multiple Electrons • These graphs can reveal which electrons are easy to remove and which are hard • Read carefully, they, can also reveal the details of the electron structure. 1s1 1s2 IE (kJ/mol) 2s1 0 1rst 2nd 3rd Electron Number

  11. Ionisation energies and group numbers Successive ionization energies for potassium Potassium is in group 1 Notice the “jump” in energy needed to remove the 2nd electron

  12. level 1 (2 electrons) level 2 (8 electrons) level 3 (8 electrons) level 4 (1 electron) Ionisation energies and group numbers Successive ionisation energies for potassium The different “jumps” are evidence for the arrangement of electrons in energy levels and sub-levels

  13. Ionisation energies and group numbers Which group is this element in? Group 4 Notice the “jump” in energy needed to remove the 5th electron

  14. Ionisation energies and group numbers Which group is this element in? Group 2 Notice the “jump” in energy needed to remove the 3rd electron

  15. Ionisation energies and group numbers Which group is this element in? Group 3 Notice the “jump” in energy needed to remove the 4th electron

  16. Ionisation energies and group numbers Which group is this element in? Group 5 Notice the “jump” in energy needed to remove the 6th electron

  17. Ionisation energies and group numbers Which group is this element in? Group 1 Notice the “jump” in energy needed to remove the 2nd electron

  18. Credits • With the inspiration and original work of Nigel Saunders, Creative Chemistry

More Related