# Question 5c707

Jul 5, 2016

Here's how you can do that.

#### Explanation:

Ammonium phosphate, ("NH"_color(red)(4))_color(blue)(3)"PO"_4, is an ionic compound made up of ammonium cations, ${\text{NH}}_{4}^{+}$, and phosphate anions, ${\text{PO}}_{4}^{3 -}$.

As you can see from the compound's chemical formula, one formula unit of ammonium phosphate contains

• three ammonium cations, $\textcolor{b l u e}{3} \times {\text{NH}}_{4}^{+}$
• one phosphate anion, $1 \times {\text{PO}}_{4}^{3 -}$

This of course means that one mole of ammonium phosphate will contain $\textcolor{b l u e}{3}$ moles of ammonium cations and $1$ mole of phosphate anions.

Now, each ammonium cation is made up of

• one atom of nitrogen, $1 \times \text{N}$
• four atoms of hydrogen, $\textcolor{red}{4} \times \text{H}$

Since one mole of ammonium cations will contain $\textcolor{red}{4}$ moles of hydrogen atoms, it follows that one mole of ammonium phosphate will contain a total of

color(blue)(3) color(darkred)(cancel(color(black)("moles NH"_4^(+)))) * (color(red)(4)color(white)(a)"moles of H")/(1color(darkred)(cancel(color(black)("mole NH"_4^(+))))) = color(green)(|bar(ul(color(white)(a/a)color(black)("12 moles of H")color(white)(a/a)|)))

Therefore, you can say that every mole of ammonium phosphate contains a total of $12$ moles of hydrogen atoms.

You can expand this to say that for any number of moles of ammonium chloride given to you, $n$, the number of moles of hydrogen atoms can be found by multiplying $n$ by $12$

n color(red)(cancel(color(black)("moles"color(white)(a)("NH"_4)_3"PO"_4))) * "12 moles H"/(1color(red)(cancel(color(black)("mole"color(white)(a)("NH"_4)_3"PO"_4)))) = (12 * n)color(white)(a)"moles H"#