# What would be the formula for diphosphorus pentoxide?

May 11, 2016

${P}_{2} {O}_{5}$ as written, but this is an empirical formula.

#### Explanation:

${P}_{2} {O}_{5}$ is of course an empirical formula. The actual oxide is ${P}_{4} {O}_{10}$, with an adamantane structure.

May 11, 2016

Here's my thought process:

• From name: phosphorus $\to$ $\text{P}$
• "di" $\to$ $2$
• From name: oxide $\to$ $\text{O}$
• Anion stem: "ox"
• "pent" (instead of "penta", since "ox" starts with a vowel) $\to$ $5$

$\to$ ${\text{P"_2"O}}_{5}$ (empirical formula)