[4] AMPHOTERIC SALTS HYDROLYSIS :

Example of amphoteric salts  NaHS, NaHCO₃, Na₂HPO₄, NaH₂PO₄

_{Both reaction will support each other extent of hydrolysis and extent of dissociation is same.}

ILLUSTRATIVE EXAMPLE: Calculate pH of solution of

(1) 100 ml 0.1M H₃PO₄ + 100 ml 0.1M NaOH.

(2) 100 ml 0.1M H₃PO₄ + 200 ml 0.1M NaOH.

(3) 100 ml 0.1M H₃PO₄ + 300 ml 0.1M NaOH.

(4) 100 ml 0.1M H₃PO₄ + 400 ml 0.1M NaOH.

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