Question

ammonium phosphate ((nh4)3po4) is an important ingredient in many solid fertilizers. it can be made by reacting aqueous phosphoric acid (h3po4) with liquid ammonia. calculate the moles of ammonia needed to produce 0.050 mol of ammonium phosphate. be sure your answer has a unit symbol, if necessary, and round it to the correct number of significant digits.

Explanation:

Step1: Write the balanced chemical equation

$H_3PO_4 + 3NH_3=(NH_4)_3PO_4$

Step2: Determine the mole - ratio

From the balanced equation, the mole - ratio of $NH_3$ to $(NH_4)_3PO_4$ is 3:1.

Step3: Calculate the moles of ammonia

Let $n_{NH_3}$ be the moles of ammonia and $n_{(NH_4)_3PO_4}$ be the moles of ammonium phosphate. Using the mole - ratio $\frac{n_{NH_3}}{n_{(NH_4)_3PO_4}}=\frac{3}{1}$. Given $n_{(NH_4)_3PO_4} = 0.050\ mol$, then $n_{NH_3}=3\times n_{(NH_4)_3PO_4}$.
$n_{NH_3}=3\times0.050\ mol = 0.15\ mol$

Answer:

$0.15\ mol$