Question

If phosphorous acid, tetrathionic acid, and pyrophosphoric acid have number of acidic hydrogen per molecule respectively as $x,y,\text{and}z$, then find the value of $x+y-z$.

Answer 1

$\text{Phosphorous acid}\left(H_{3}P{O}_3\right)\text{is dibasic}\therefore x=2$


$\text{Tetrathionic acid}\left(H_2{S}_4{O}_6\right)\text{is dibasic}\therefore y=2$


$\text{Pyrophosphoric acid}\left(H_4{P}_2{O}_7\right)\text{is tetrabasic}\therefore z=4$
$\text{So,}x+y-z=2+2-4=0$