# What is P_2O_5?

Jul 17, 2017

Well phosphorus pentoxide is a dense free-flowing white powder, that has a melting point of $340$ ""^@C....

#### Explanation:

It reacts with water to give phosphoric acid.......

${P}_{4} {O}_{10} + 6 {H}_{2} O \rightarrow 4 {H}_{3} P {O}_{4}$

........and in fact it is so hygroscopic, that when you use a tin that has been already been opened, you find a syrupy crust of phosphoric acid that you must dig beneath to get at the good stuff.

The molecular formula is ${P}_{4} {O}_{10}$; sometimes it is formulated as ${P}_{2} {O}_{5}$, i.e. as its empirical formula........