Question

A 100ml solution is prepared by mixing 8.2 g of $\sf Na_3PO_4$ and 4.5625 g of HCl . If $\sf K_{a_1} , K_{a_2} \: and \;K_{a_3}$ of $\sf H_3PO_4$ are $10^{-5} , 10^{-8} \; and \; 10^{-13}$ respectively the pH of the prepared solution would be? ​

Answer 1

Answer:

The formula for the hydroxide ion concentration is,

 [OH]−=Va+VbNbVb−NaVa.

Substitute values in the above expression, 

[OH]−=0.1+0.10.6×0.1−0.5×0.1=0.05 M.

pOH=−log[OH]−=−log0.05=1.3.

pH=14−pOH=14−1.3=12.7.

Answer 2

the ph of the solution is 12.4

solution is basic