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Question
How many salts can be obtained from ortho phosphoric acid? Is there any difference in the salts formed by the acid?
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Solution
Ortho phosphoric acid is H3PO4 i.e; a tribasic acid has three replaceable hydrogen atoms so it forms three series of salts, namely two acid salts and a normal salt, with NaOH as:
NaOH + H3PO4 → NaH2PO4 + H2O
Acid salt
( Monosodium hydrogen salt )
2NaOH + H3PO4 → Na2HPO4 + 2H2O
Acid salt
( Disodium hydrogen phosphate )
3NaOH + H3PO4 → Na3PO4 + 3H2O
Normal salt
( Sodium Phosphate )
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