Question

One of the acid listed below is formed only from $P_2{O}_3$, the rest are formed from $P_2{O}_5$. Acid formed from $P_2{O}_3$ is :

• A. $HP{O}_3$
• B. $H_2{P}_2{O}_7$
• C. $H_{2}P{O}_4$
• D. $H_{3}P{O}_3$

Answer 1

Answer: (D)

$H_{3}P{O}_3$

When $P_2{O}_3$ reacts with $H_{2}O$, it forms $H_{3}P{O}_3$.

$P_2{O}_3+3H_{2}O\to 2H_{3}P{O}_3$

Hence, option D is correct.