1. Chemistry of Group 1 Elements. (The Alkali Metals) For grades 9-12 State Standard 2.0 Interactions of Matter. Gary Lennon

2. Group 1 Elements. Li LithiumLithium Na SodiumSodium K PotassiumPotassium Rb RubidiumRubidium Cs CesiumCesium Fr FranciumFrancium The Most reactive family of metals. Reactivity increases DOWN the group.DOWN Why?

3. Group 1 Elements. All Group 1 elements share the same electron configuration in their outer energy level. All are ns 1, where n = energy level currently filling. All have a great desire to lose this one electron and thereby attain a stable full outer energy level. Reactivity increases down the group because of reduced nuclear shielding.

4. The more energy levels there are between the single valence electron and the nucleus, the more that valence electron is shielded from the forces holding the atom together. This means it will lose that electron more readily. If we look back at the videos, we can now hazard a good guess at which of those elements is lowest in the group.lowest

5. All Group 1 metals are too reactive to exist in nature as the isolated element. Most sodium is found as sodium chloride (salt).sodium chloride Analogous to the reactivity of sodium, so chlorine (Group 17, Halogens) is exceptionally reactive but for a different reason. In this case, chlorine has an ns 7 configuration, it needs 1 more electron to be stable.