CHM 2353 Lecture Notes - Lecture 11: Covalent Bond, Magnesium Oxide, Hard Water

• School: University of Ottawa
• Department: Chemistry
• Course: CHM 2353
• Professor: Muralee Murugesu

Document Summary

Harder acids than group 1: higher charge density. Low densities but more dense than group 1. Stronger metallic bonding than group 1 - higher melting temperatures, bond strength does not decrease down the group. Very reactive, but less reactive than group 1. 1st ionization energy decreases down the group (size increases) Don"t want to remove electrons from the full p orbital. Group 2 elements are often found in the +2 oxidation state. M (s) + 2 h2o (l) > h2 (g) + m(oh)2 (s) Ba, ca, sr react with cold water (ba is the most vigorous) Will form oxides (o2-) slowly, unless ignites, in which case oxides are formed rapidly: 2 m (s) + o2 (g) > 2 mo (s) *ba is the exception by forming both the oxide (o2-) and the peroxide (o22-) These oxides (except mg) are water soluble and form basic hydroxides upon reaction with water: Mo (s) + h2o (l) > m(oh)2 (s)