\(\quad\quad\quad\quad\quad\quad\quad\quad\downarrow+3 {H}_{2} {O}\)
\(\quad\quad\quad\quad\quad\quad\quad\quad{H}_{3} {PO}_{4}+3 {HCl}\)
\([Image]\)
all hydrogens are ionisable
\(\therefore\) Ans is zero.