CHEM101 Lecture Notes - Lecture 13: Alkali Metal, Valence Electron, Metallic Bonding

• School: University of Alberta
• Department: Chemistry
• Course: CHEM101
• Professor: Yoram Apelblat

Document Summary

Alkali metals are the largest elements in their respective periods and their valence electron configuration is ns1: the valence e is relatively far from the nucleus, resulting in weak metallic bonding. They can be cut easily with a knife. Alkali metals have lower melting and boiling points than any other group of metals. Alkali metals have lower densities than most metals. Alkali metals are powerful reducing agents: they always occur in nature as +1 cations rather than as free metals. Alkali metals reduce halogens to form ionic solids: 2e(s) + x2 2ex(s) (x = f, cl, br, i; e is the alkali metal). Alkali metals reduce h2 to form ionic hydrides: Alkali metals reduce o2 in air, and tarnish rapidly. Gradations in bond type among period 3 and group 4a elements. But how can we predict how elements bond: lewis electron-dot symbols. The element symbol = nucleus and inner electrons.