CHEM 1A: Challenge Problem Set 10
1. Consider an aqueous solution of magnesium chloride with a concentration of 3.299 M. What volume
of this solution (in L) would be needed to supply 61.17 grams of magnesium chloride as a solute?
2. Consider the reaction of sulfuric acid with potassium hydroxide. If 12.58 mL of aqueous 1.724
M sulfuric acid is required to reaction with 40.00 mL of aqueous potassium hydroxide solution, what
is the concentration of the potassium hydroxide solution?
3. Consider the reaction of sodium hydroxide with an unknown triprotic acid (H 3A):
4. 3 NaOH(aq) + H3A(aq) ---> Na3A(aq) + 3 H2O(l)
A titration is performed by adding 1.198 M sodium hydroxide to 3.298 grams of H3A dissolved in water. If
55.06 mL of sodium hydroxide were required to fully react with all of the triprotic acid, determine the molar
mass of the unknown acid (in g/mol).