Question

How many grams of H2 are required to produce 18.5 g of NH3

Answer 1

Step-by-step explanation:

We are given: mass of NH3 = 18.5 g

We know: molar mass of NH3 = 17.031 g/mol

: molar mass of H2 = 2.016 g/mol

We first determine the number of moles of NH3:

`\begin{gathered} n\text{ = }(m)/(M) \\ \\ \text{ = }(18.5)/(17.031) \\ \\ \text{ = 1.086 mol} \end{gathered}`

We then determine the number of moles of H2 from the number of moles of NH3:

`\begin{gathered} n(H2)\text{ = }(3)/(2)* n(NH3) \\ \\ \text{ = }(3)/(2)*1.086 \\ \\ \text{ = 1.629 mol} \end{gathered}`

We then determine mass of H2 required:

`\begin{gathered} n\text{ = }(m)/(M) \\ \\ \therefore\text{ m = nM } \\ \\ \text{ = 1.629}*2.016 \\ \\ \text{ = 3.28 g} \end{gathered}`

Answer:

grams of H2 required = 3.28 g