Aqueous hydrobromic acid (HBr) reacts with solid sodium hydroxide (NaOH) to produce aqueous sodium bromide (NaBr) and liquid water (H2O).

Question

What is the theoretical yield of sodium bromide formed from the reaction of 4.0g of hydrobromic acid and 3.4g of sodium hydroxide? Round your answer to 2 significant figures.

Answer 1

HBr(aq) + NaOH(aq) ==> NaBr(aq) + H2O(l) ... balanced equation

Find the limiting reactant. Divide moles of each reactant by the corresponding coefficient in the balanced equation (1 for each in this case) and whichever is lower is the limiting reactant.

For HBr: 4.0 g HBr x 1 mol HBr / 80.9 g = 0.0494 mols HBr

For NaOH: 3.4 g NaOH x 1 mol NaOH / 40 g = 0.085 mols NaOH

HBr is limiting and will determine the yield of NaBr.

Theoretical yield of NaBr:

0.0494 mols HBr x 1 mol NaBr / mol HBr x 103 g NaBr / mol = 5.1 g NaBr (2 sig. figs.)