1 / 18

Electron Configurations

Electron Configurations. The Big Questions. How are electrons arranged in atoms? How can we represent the arrangement of electrons in atoms?. More Energy. n = 3. n = 4. n = 2. n = 1. Nucleus. Simple model of a potassium atom. Electron Structure.

ursula
Download Presentation

Electron Configurations

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. Electron Configurations

  2. The Big Questions • How are electrons arranged in atoms? • How can we represent the arrangement of electrons in atoms?

  3. More Energy n = 3 n = 4 n = 2 n = 1 Nucleus Simple model of a potassium atom Electron Structure • In a neutral atom, electrons = atomic number. • Electrons are arr. into energy levels.

  4. Electron Structure • Energy levels are divided into sublevels. • Four types: • s • p • d • f

  5. Electron Structure • Sublevels are made of orbitals. • Orbital – a zone of probability. • Each orbital can hold up to 2 electrons. • Sublevel type / # of orbitals / # of e- • s / 1 orbital / 2 electrons • p / 3 orbitals / 6 electrons • d / 5 orbitals / 10 electrons • f / 7 orbitals / 14 electrons

  6. s, p, d, and f orbitals

  7. Energy Level Sublevel Orbitals Electrons n = 1 1s 1 2 2s 1 2 n = 2 2p 3 6 3s 1 2 n = 3 3p 3 6 3d 5 10 4s 1 2 4p 3 6 n = 4 4d 5 10 4f 7 14

  8. Electron Structure • Aufbau Principle – Electrons fill lowest sublevels first. • Aufbau = German for “building up”. • Energy levels overlap. • Expected order: • 1s2s 2p3s 3p 3d4s 4p 4d 4f... • Actual order: • 1s2s 2p3s 3p4s3d4p5s4d5p6s4f...

  9. 6p 5d 4f 6s 5p 4d 5s 4p Increasing Energy 3d 4s 3p 3s 2p 2s 1s Aufbau Principle

  10. 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 6s 6p 6d 7s 7p Electron Configuration 1s

  11. 1st row 1s 1s Row number – 1 2nd row 2s 2p 3rd row 3s 3p 4th row 4s 3d 4p 5th row 5s 4d 5p 6th row 6s 5d 6p 7th row 7s 6d 7p 6th row 4f 7th row 5f Row number – 2 Electron Configurations

  12. 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 6s 6p 6d 7s 7p Electron Configurations • What is the electron configuration for H? • H has 1 e- • What is the electron configuration for He? • He has 2 e- 1s1 1s2

  13. 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 6s 6p 6d 7s 7p Electron Configurations • What is the e- config. for lithium? • What is the e- config. for oxygen? 1s2 2s1 1s2 2s2 2p4

  14. 1s 2s 2p 3s 3p 3d 4s 4p 4d 4f 5s 5p 5d 5f 6s 6p 6d 7s 7p Electron Configurations • What is the e- config. for iron? • What is the e- config. for iodine? 2s2 3d6 1s2 2p6 3s2 3p6 4s2 2s2 3d10 5s2 4d10 5p5 1s2 2p6 3s2 3p6 4s2 4p6

  15. 1s2 2s2 2p6 1s2 2s2 2p6 Noble Gas Core Configuration • Noble gases: Group 8A • He, Ne, Ar, Kr, Rn, Xe, element 118 • e- configuration for Mg (element 12): • 1s2 2s2 2p6 3s2 • e- configuration for Ne (element 10): • 1s2 2s2 2p6 • Noble gas core configuration for Mg: • [Ne] 3s2

  16. Noble Gas Core Configuration • To write NGCC: • Find your element. • Find the noble gas (Group 8A) before your element. • Write the noble gas in brackets. • Add electrons to the noble gas until you reach your element. • Do not start at 1s. • Start with the s-type sublevel on the same row as your element.

  17. Noble Gas Core Configuration • Write the NGCC for bismuth (element 83) • Previous noble gas: xenon (element 54) • Bismuth is on row 6, so start with 6s2. • Brings the total up to 56. • Proceed to 4f14. • Brings the total up to 70. • Proceed to 5d10. • Brings the total up to 80. • Proceed to 6p3. • Brings the total up to 83. • Done! [Xe] 6s2 4f14 5d10 6p3

  18. Noble Gas Core Configuration • Write the NGCC for radium (element 88) • Previous noble gas: radon (element 86) • Radium is on row 7, so start with 7s2 • Brings the total up to 88. • Done! [Rn] 7s2

More Related