Rubidium hydroxide is the inorganic compound with the formula RbOH. It consists of rubidium cations and one hydroxide anions. It is a colorless solid that is commercially available as aqueous solutions from a few suppliers. Like other strong bases, rubidium hydroxide is highly corrosive. Rubidium hydroxide is formed when rubidium metal is dissolved in water.
Molar mass：102.475 g·mol−1
Density：3.1 g/mL at 25 °C
Melting point：382 °C (720 °F; 655 K)
Boiling point：1,390 °C (2,530 °F; 1,660 K)
Solubility in water：173 g/100 mL (30 °C)
Solubility：soluble in ethanol
Rubidium hydroxide is rarely used in industrial processes because potassium hydroxide and sodium hydroxide can perform nearly all the same functions of rubidium hydroxide. Metal oxide catalysts are sometimes modified with rubidium hydroxide.