Is Aluminium Fluoride Soluble In Water?

Aluminium fluoride (AlF3) is sparingly soluble in water. The solubility of AlF3 in water depends on various factors such as temperature, pH, and the presence of other ions. At room temperature, only a small amount of AlF3 (~0.24 g/100 mL) dissolves in water, resulting in a slightly acidic solution due to hydrolysis.

However, the solubility of AlF3 can be increased by adjusting the pH of the solution. Acidic solutions with a low pH value can dissolve more AlF3 than neutral or alkaline solutions. Additionally, complexing agents such as fluoride ions can also increase the solubility of AlF3 in water by forming soluble complexes with aluminium ions.

Moreover, the solubility of AlF3 increases with increasing temperature. At higher temperatures, more AlF3 can dissolve in water, however, the solubility still remains relatively low. In general, Aluminium fluoride is considered to be relatively insoluble in water compared to other fluorides like sodium fluoride or potassium fluoride.

Overall, while AlF3 is technically soluble, its solubility is limited and dependent on various factors, making it difficult to dissolve significant amounts of AlF3 in water under normal conditions.