Tabla de Contenidos
Ba (s) + 2 H 2 O (l) –> Ba(OH) 2 (aq) + H 2 (g)
Reactivity increases as the mass within the group increases, so magnesium does not react with cold water, but reacts slowly with hot water to produce magnesium hydroxide and hydrogen gas.
Common Characteristics of Alkaline Earth Metal Compounds
Excluding beryllium, the properties of the compounds of the rest of the elements of the group are mainly summarized in two:
- Ionic Character: Alkali metal ions have an oxidation number of +2, and their compounds are mostly colorless, stable, ionic solids unless bound by a colored anion. Most of the bonds in alkaline earth metal compounds are ionic in character, but covalent behavior is particularly apparent in magnesium compounds.
- Ion Hydration: Alkaline earth metal salts are almost always hydrated. Thus, for example, calcium chloride can be prepared as hexahydrate, tetrahydrate, dihydrate and monohydrate, in addition to the anhydrous form. As the charge density of the metal decreases, so does the hydration number.
Sources
- Rayner-Canham, G. (2000). Descriptive Inorganic Chemistry (2nd ed.). Pearson Education
