I certainly know that bases which can be dissolved in water are called alkalies, for example, NaOH and KOH. At the same time, Fe(OH)3, Al(OH)3 are not alkalies because they don't dissolve in water. Why don't they dissolve in water?
I suppose the solubility rules might have a part in this......Well, then what accounts for the solubility rules themselves? Or is it because of some charge density concept about the force of attraction between the anions and the hydroxide radicals together with the water molecule?
Thanks for your answers.....
Actually they do, just not very much. Even the most insoluble compound that exists will dissociate into ions at some measurable amount.
But the simple explanation deals with the solubility of hydroxide compounds. Think back to the solubility rules. "All hydroxides are insoluble, except for the group IA hydroxides ..."
Since oxygen has the second highest electronegativity, the forces holding these compounds together is greater than the attractive forces that water exerts on the metals or OH- group, except for the alkali metals.
The alkali metal ions are very large which will allow them to accommodate a larger number of water molecules, which, in turn, will separate the metal hydroxide allowing it to dissolve.
some bases are called as alkalies as they completely dissolve in water without leaving any residue.
and the others donot dissolve in water
how about the ph factor
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