A student mixes 23.1 g of hydrochloric acid with 16.2 g of ammonium hydroxide and observes them react to form water and ammonium chloride. The reaction goes to completion and 30.5 g of ammonium chloride was formed. How many grams of water was produced?

8.33g

Explanation:

According to the question, the balanced chemical equation of this reaction is as follows:

HCl + NH4OH -> NH4Cl + H2O

This means it takes 1 mole of HCl and NH4OH each to produce 1 mole of NH4Cl and H20 respectively.

To determine the limiting reactant in this reaction, we calculate the number of moles of each reactant by dividing by their respective molar mass

Molar mass of HCl = 1+35.5 = 36.5g/mol

Molar mass of NH4OH = 14+4+16+1= 35g/mol

-Number of moles of HCl= 23.1/36.5 = 0.6328moles

-Number of moles of NH4OH= 16.2/35 = 0.4628moles

Next, we divide each number of mole by their respective stoichiometric coefficient. That is;

HCl= 0.6328/1 = O.6328

NH4OH= 0.4628/1 = 0.4628

The reactant with the smallest number of mole is the limiting reactant i.e. NH4OH, hence it will determine the number of moles of H2O produced.

Mole ratio: 1mole of NH4OH produced 1 mole of H2O

0.4628moles of NH4OH will produce 0.4628 × 1 = 0.4628 moles of H2O.

We then calculate the mass of H2O produced from its number of moles:

Molar mass of H2O = 2+16= 18g/mol

Mass of H2O = 0.4628 × 18

Mass of H2O = 8.3304

Therefore, 8.33grams of water was produced.