Which of the following oxoacids of phosphorus is a reducing agent and a monobasic acid as well?
Which of the following oxoacids of phosphorus is a reducing agent and a monobasic acid as well?
$\mathrm{H}_4 \mathrm{P}_2 \mathrm{O}_5$
$\mathrm{HPO}_3$
$\mathrm{H}_3 \mathrm{PO}_3$
$\mathrm{H}_3 \mathrm{PO}_2$
Solution
Acids which contain $\mathrm{P}-\mathrm{H}$ bonds have strong reducing properties. Hypophosphorus acid $\left(\mathrm{H}_3 \mathrm{PO}_2\right)$ is a good reducing agent as it contains two $\mathrm{P}-\mathrm{H}$ bonds. It has one $\mathrm{P}-\mathrm{OH}$ bond, so it is monobasic.
