Amphoteric hydroxides react with both alkalies and acids.
Amphoteric hydroxides react with both alkalies and acids. ‘Which of the following group 2 metal hydroxides is soluble in sodium hydroxide ? (a) Be(OH)2 (b) Mg(OH)2 (c) Ca(OH)2 (d) Ba(OH)2
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Mg(OH)2 is the only soluble metal hydroxide in sodium hydroxide. The other metal hydroxides listed (Be(OH)2, Ca(OH)2, and Ba(OH)2) are insoluble in sodium hydroxide. This is because metal hydroxides are only soluble in strong alkali solutions. The solubility of metal hydroxides decreases as the size of the metal ion increases. Sodium hydroxide has a high concentration of hydroxide ions, making it a strong alkali solution, so Mg(OH)2 is the only metal hydroxide soluble in sodium hydroxide solution.
