1 / 17

Periodic Groups and Trends

Periodic Groups and Trends. Periodic Table. Periodicity: regular variations (or patterns) of properties with increasing atomic weight. Both chemical and physical properties vary in a periodic (repeating pattern). Group: vertical column of elements (“family”)

miron
Download Presentation

Periodic Groups and Trends

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. Periodic Groups and Trends

  2. Periodic Table • Periodicity: regular variations (or patterns) of properties with increasing atomic weight. Both chemical and physical properties vary in a periodic (repeating pattern). • Group: vertical column of elements (“family”) • Period: horizontal row of elements

  3. Activity: get out your black and white copy of the periodic table.

  4. On one side, color and label the metals, nonmetals, and metalloids. Another name for “metalloid” is “semi-metal”.

  5. Color and label the groups/families of elements on the other side of your paper. Remember to create a legend. noble gases Transition metals alkali metals halogens alkaline earth metals lanthanides actinides

  6. PERIODIC GROUPS • alkali metals • alkaline earth metals • transition metals • halogens • noble gases • lanthanides • actinides

  7. Alkali Metals • Group 1 on periodic table • Very reactive • Soft solids • Readily combine with halogens (ex. NaCl) • Tendency to lose one electron (to become an ion)

  8. Alkaline Earth Metals • Group 2 on periodic table • Abundant metals in the earth • Not as reactive as alkali metals • Higher density and melting point than alkali metals

  9. Transition Metals • Groups 3-12 on periodic table Important for living organisms (think vitamins: multivitamins (they have iron, zinc, chromium, etc.)

  10. Halogens • Group 7A on periodic table (***or GROUP 17) • “Salt former” – combines with groups 1 and 2 to form salts (ionic bonds)

  11. Noble Gases • Group 8 on periodic table (** or GROUP 18) • Relatively inert, or nonreactive • Gases at room temperature

  12. Lanthanides • Part of the “inner transition metals” • Soft silvery metals • Tarnish readily in air • React slowly with water

  13. Actinides • Radioactive elements • Part of the “inner transition metals”

  14. Atomic Radii

  15. Atomic Radii • Trend: increases down a group • WHY??? • The atomic radius gets bigger because electrons are added to energy levels farther away from the nucleus.

  16. Atomic Radii • Trend: decreases across a period • WHY??? • As the # of protons in the nucleus increases, the positive charge increases and as a result, the “pull” on the electrons increases.

  17. Summing Up Periodic Trends

More Related