Chemical Properties
clear colorless solution
Physical properties
Grayish-white orthogonal crystals; hygroscopic; density 3.2 g/cm
3; melts at 301°C; very soluble in water (100 g/100 mL at 15°C), the solution highly alkaline; soluble in ethanol.
Uses
Rubidium hydroxide is an important intermediate in the synthesis of other rubidium compounds and can be used as a catalyst in oxidative chlorination reactions. It is also used in photography and storage batteries. Adding Rubidium hydroxide to fireworks to give it a violet color.
Definition
ChEBI: Rubidium hydroxide is an alkali metal hydroxide and a rubidium molecular entity.
Preparation
Rubidium hydroxide may be obtained as an intermediate in recovering rubidium metal from mineral lepidolite (see Rubidium). In the laboratory it may be prepared by adding barium hydroxide to a solution of rubidium sulfate. The insoluble barium sulfate is separated by filtration:
Rb
2SO
4 + Ba(OH)
2 → 2RbOH + BaSO
4Preparation should be in nickel or silver containers because rubidium hydroxide attacks glass. The solution is concentrated by partial evaporation. The commercial product is usually a 50% aqueous solution.
General Description
A clear aqueous solution. Very caustic. Very irritating to skin and eyes. Used in electric storage batteries.
Air & Water Reactions
Absorbs carbon dioxide from the air. May generate large amounts of heat when diluted with water.
Reactivity Profile
A strong base. Forms caustic solution in water [Merck 11th ed. 1989].
Hazard
Strong irritant to tissue.
Health Hazard
TOXIC; inhalation, ingestion or skin contact with material may cause severe injury or death. Contact with molten substance may cause severe burns to skin and eyes. Avoid any skin contact. Effects of contact or inhalation may be delayed. Fire may produce irritating, corrosive and/or toxic gases. Runoff from fire control or dilution water may be corrosive and/or toxic and cause pollution.
Fire Hazard
Non-combustible, substance itself does not burn but may decompose upon heating to produce corrosive and/or toxic fumes. Some are oxidizers and may ignite combustibles (wood, paper, oil, clothing, etc.). Contact with metals may evolve flammable hydrogen gas. Containers may explode when heated.
Safety Profile
Moderately toxic by ingestion. A powerful, corrosive irritant to skin, eyes, and mucous membranes. When heated to decomposition it emits toxic fumes of RbzO. See also POTASSIUM HYDROXIDE and RUBIDIUM.
