Question

Consider the following reaction: Li3N (s) + 3H2O (l) → NH3 (g) + 3LiOH (l) If you need to make 24 g LiOH, how many grams of Li3N must you react with excess water?

Answer 1

Answer:

11.63 g

Explanation:

The reaction given is balacend:

Li₃N(s) + 3H₂O(l) → NH₃(g) + 3LiOH(l)

The molar masses of the interest compounds are:

Li₃N = 34.83 g/mol

LiOH = 23.95 g/mol

By the stoichiometry of the reaction:

1 mol of Li₃N ---------- 3 moles of LiOH

Transforming these values to mass multiplying the number of moles by the molar mass:

34.83 g of Li₃N ------------- 71.85 g of LiOH

x                        ------------- 24 g of LiOH

By a simple direct three rule:

71.85x = 835.92

x = 11.63 g of Li₃N