Question

Given are $H_3{PO}_2,H_3{PO}_3,H_3{PO}_4$ and $H_4{P}_2{O}_7$

Which of the above oxoacids results into two series of salts?

• A. $H_3{PO}_2$
• B. $H_3{PO}_3$
• C. $H_3{PO}_4$
• D. $H_4{P}_2{O}_7$

Answer 1

The correct option is B $H_3{PO}_3$

Phosphorus acid ($H_3{PO}_3$) is a diprotic acid. It forms two series of salts such as $Na{H}_2{PO}_3$ and ${Na}_{2}H{PO}_3$ but none of the type ${Na}_3{PO}_3$ with $NaOH$. Its structure is as shown.