If it requires 48.3 milliliters of 0.55 molar nitric acid to neutralize 15.0 milliliters of barium hydroxide, solve for the molarity of the barium hydroxide solution. Show all of the work used to solve this problem.

Unbalanced equation: Ba(OH)2 + HNO3 Ba(NO3)2 + H2O

Question

If it requires 48.3 milliliters of 0.55 molar nitric acid to neutralize 15.0 milliliters of barium hydroxide, solve for the molarity of the barium hydroxide solution. Show all of the work used to solve this problem.

Unbalanced equation: Ba(OH)2 + HNO3  Ba(NO3)2 + H2O

anonymous · Answer

The first thing to note is that the barium ion is 2+ whereas the nitrate ion is -1. So nitric acid only has one hydrogen ion to donate whereas barium hydroxide has two hydroxyl ions. This means you would need twice as much nitric acid than you might expect: Ba(OH)2 + 2 HNO3. The number of moles of nitric acid is 0.0483 multiplied by 0.55M or 0.0266 moles. Dividing this number of moles by 15 ml or 0.015l gives 1.77M but there are two hydroxides per Barium hydroxide molecule and so the concentration is half or 0.886M.$$ Ba(OH)2 + 2HNO3- \rightarrow Ba(NO3)2  2H2O$$