Chapter 5 Notes The Periodic Table

I. Scientist A. Antoine Lavaiser- grouped known elements into categories he called metals, nonmetals, and gases in 1789.

I. Scientist B. Dmitri Mendeleev- In 1860, grouped elements based on solitaire.  1. He arranged elements in increasing mass.  2. Left spaces for new elements to be discovered.

II. Modern Periodic Table A. Periodic Law- pattern of properties that arrange the elements on the table B. Periods- each row on the table

II. Modern Periodic Table Groups- columns on the table  1. Properties of elements to repeat in a predictable way  2. Similar electron configurations determine the chemical properties of the element  3. There are 18 groups

II. Modern Periodic Table Element Symbols  1. Solids- black symbols  2. Liquids- purple symbols  3. Gases- red symbols  4. White symbols do not occur naturally in nature

II. Modern Periodic Table Classes of Elements  1. Metals Good conductors Except mercury, metals are solids at room temp Malleable and ductile

II. Modern Periodic Table  2. Transition Metals- groups 3-12 Form compounds with distinct colors

II. Modern Periodic Table  3. Nonmetals Poor conductors Most gases at room temp Solids are brittle Fluorine, group 17, MOST REACTIVE Group 18 LEAST REACTIVE

II. Modern Periodic Table  4. Metalloids Properties between metals and nonmetals (green in the back of the book)

III. Variation Across Periods 1. From LEFT to RIGHT elements become less metallic and more nonmetallic is their properties 2. Most reactive metals are on the LEFT 3. Most reactive nonmetals are on the RIGHT in Group 17

IV. Groups Valence electrons- electrons in the highest occupied energy levels. The number of valence electrons is the same as the GROUP NUMBER

IV. Groups A. Alkali Metals- Group 1A  Have one valence electrons  Extremely reactive  Reactivity increases from top to bottom

IV. Groups B. Alkaline Earth Metals- Group 2A  Have 2 valence electrons  Reactivity is based on their reactivity with water Ex: Magnesium (Mg)- used for photosynthesis, frames of bikes, and backpacks Ex: Calcium (Ca)- used for teeth and bones

IV. Groups C. Boron family- Group 3A  Have 3 valence electrons Ex: Aluminum is the MOST ABUNDANT metal in the Earth’s crust Ex: Boron is used to make lab glassware

IV. Groups D. Carbon Family- Group 4A  4 valence electrons  most compounds in your body contain carbon  Silicon is the 2 nd most abundant metal in the earth’s crust

IV. Groups E. The Nitrogen Family- Group 5A  5 valence electrons  Nitrogen and Phosphorous are the most important in the group Ex: fertilizers contain phosphorous

IV. Groups F. Halogens- Group 7A  7 valence electrons  Highly reactive nonmetals  Fl is the most reactive Ex: Iodine is important for your thyroid gland

IV. Groups G. Noble Gases- Group 8A  Colorless, Odorless, and extremely unreactive Ex: All used in neon lights except radon

Quiz 6 1. ________ are columns in the periodic table and there ______ total. 2. _______ are located on the left side of the periodic table and are known for being good conductors. 3. ______ is considered to be the “big daddy” on the periodic table because it is the most reactive element. 4. _________ symbols do not occur naturally in nature. 5. ________ _________ are located between groups 3-12 and when they form compounds make distinctive colors (ex. Stain glass windows). 6. _________ group is considered to be the least reactive group in the periodic table. 7. Give 2 characteristics of nonmetals.