Question

A sample of ammonium phosphate $(N{H}_4{)}_{3}P{O}_4$ contains $3.18mol$ of hydrogen atoms. The number of moles of oxygen atoms in the sample is:

• A. $0.265mol$
• B. $0.795mol$
• C. $1.06mol$
• D. $4.00mol$

Answer 1

The correct option is C $1.06mol$

In $(N{H}_4{)}_{3}P{O}_4$
Ratio of number of moles of Hydrogen atoms to Oxygen atoms is $12:4=3:1$

So,
$H/O=3/1$
Given, moles of hydrogen atoms = 3.18 mol
$\therefore$ = $3.18/O=3/1$
moles of oxygen atom $O=3.18/3$
Moles of $O$ atoms = 1.06 mol