Answer to Question #187170 in Organic Chemistry for Eudoxia

Question

If 16.41 mL of aqueous NaOH is required to neutralise 20 mL of potassium hydrogen phthalate solution described in question 4 above, what is the molarity of the aqueous sodium hydroxide? Show your calculations as required below:

a- Calculate the number of moles of KHC8H4O4 used in the titration.

b- Using the balance reaction equation, find the number if moles of NaOH that reacted.

c- Calculate the molarity of the NaOH solution.

Answer 1

We don`t have molarity of potassium hydrogen phthalate solution (c, mol/L), but we need it.

a-The number of moles of KHC8H4O4 used in the titration c*0.02L = 0.02c mol

b-NaOH + KHC₈H₄O₄ = KNaC₈H₄O₄ + H₂O

 The number if moles of NaOH that reacted = 0.02c mol

c-The molarity of the NaOH solution = 0.02c mol / 0.01641 L=1.22c mol/L