Liquid iron-aluminium salts

Solutions which prevent the hydrolysis of salts of weak acids and bases. If the precipitate is a salt of weak acid and is slightly soluble it may exhibit a tendency to hydrolyse, and the soluble product of hydrolysis will be a base the wash liquid must therefore be basic. Thus Mg(NH4)P04 may hydrolyse appreciably to give the hydrogenphosphate ion HPO and hydroxide ion, and should accordingly be washed with dilute aqueous ammonia. If salts of weak bases, such as hydrated iron(III), chromium(III), or aluminium ion, are to be separated from a precipitate, e.g. silica, by washing with water, the salts may be hydrolysed and their insoluble basic salts or hydroxides may be produced together with an acid ... 

You can obtain an inorganic garden . For this purpose, pour 30-50 ml of a liquid glass solution into a beaker and drop crystals of cobalt, iron(II), aluminium, nickel, copper, and calcium salts into the solution. What is observed ... 

For the purpose of gravimetric analysis, where it is necessary to effect an efficient separation of solid from liquid, it is generally accepted that precipitation should be carried out slowly from dilute solution. However, some substances, such as the hydroxides and basic salts of aluminium, iron and tin, demand extremely high dilutions and excessively long times for dense particles to be produced. The method known as precipitation from homogeneous solution (PFHS) allows coarse precipitates to be produced in relatively short times (Gordon, Salutsky and Willard, 1959). 

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