1 / 24

The Periodic Table

The Periodic Table. The Big Questions. Who developed the first modern periodic table? How did he organize it, and how does this differ from the organization of the P. T. today? What are some ways in which we group elements on the P. T.? What does this tell us about the atom’s structure?.

bspinelli
Download Presentation

The Periodic Table

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. The Periodic Table

  2. The Big Questions • Who developed the first modern periodic table? • How did he organize it, and how does this differ from the organization of the P. T. today? • What are some ways in which we group elements on the P. T.? • What does this tell us about the atom’s structure?

  3. The First Modern P. T. • Developed in 1869 by Dmitri Mendeleev. • Russian chemist and inventor. • Arranged elements according to inc. atomic mass and periodicity. • Periodicity – tendency of elements to repeat properties. • Example: Lithium is a metal that reacts explosively with H2O. • This property is repeated in Na, then again in K, and so on...

  4. Dmitri Ivanovich Mendeleev

  5. The First Modern Periodic Table

  6. The First Modern P. T. • DM noticed there were “holes” where no known element would fit. • Guessed that these holes represented undiscovered elements. • Made predictions about their properties. • When discovered, these elements matched their predicted properties.

  7. Periods (Rows) • Periods – horizontal rows of elements. • All elements on a period have the same number of energy levels.

  8. Periods How many energy levels would you expect to find in atoms from the 4th row? The 5th row?

  9. Families of Elements • Families – columns or groups. • Elements in a family have similar chem. properties. • Also have same no. of valence e-. • Coincidence? (No.)

  10. Ions • Atoms can lose or gain electrons. • Ion – an atom that has become charged by gaining or losing electrons. • Cation – positive ion (lost e-) • Anion – negative ion (gained e-)

  11. 6 p+ 7 e- 6 p+ 6 e- 6 p+ 5 e- Gain 1 e- Lose 1 e- C- C C+ Ions

  12. The Octet Rule • Atoms tend to gain or lose electrons so they can have 8* valence electrons (same e- configuration as a noble gas). • Why? • 8 valence electrons = full s and p sublevel. • Extremely stable configuration.

  13. Families of the Periodic Table • Group 1A (1) • Alkali metals • 1 val. e- • Form +1 ions. • Group 2A (2) • Alkaline earth metals • 2 val. e- • Form +2 ions.

  14. Families of the Periodic Table • Groups 3B – 2B (3 – 12) • Transition metals • Have variable val. e- • Can form multiple cations. • Group 3A (13) • Boron group • 3 val. e- • Form +3 ions.

  15. Families of the Periodic Table • Group 4A (14) • Carbon group • 4 val. e- • C and Si rarely form ions. All others: +2 or +4 • Group 5A (15) • Nitrogen group • 5 val. e- • Form –3 ions (except for bismuth: +3)

  16. Families of the Periodic Table • Group 6A (16) • Chalcogens • 6 val. e- • Form –2 ions. • Group 7A (17) • Halogens • 7 val. e- • Form –1 ions.

  17. Families of the Periodic Table • Group 8A (18) • Noble gases • 8 val. e- (exc. He) • Do not form ions.

  18. Blocks s-block p-block d-block f-block

  19. Metals, Metalloids, and Nonmetals • Metals • Majority of elements are metals (80%) • Conductors of heat and electricity. • Lose electrons (form + ions). • Nonmetals • About 16 elements. • Insulators. • Tend to gain or share e- (form – ions).

  20. Metals, Metalloids, and Nonmetals • Metalloids • Between metals and nonmetals. • Semi-conductors. • Lose or share electrons.

  21. Metals, Metalloids, and Nonmetals Nonmetals Metals Metalloids

  22. Metallicity More Metallic Less Metallic Less Metallic More Metallic

  23. 1s 1s 2s 2p 3s 3p 4s 3d 4p 5s 4d 5p 6s 5d 6p 7s 6d 7p 4f 5f Electron Configs. on the P. T.

More Related