A solution of the primary standard potassium hydrogen phthalate (KHP), KHC8H4O4 , was prepared by dissolving 0.4877 g of KHP in about 50 mL of water. Titration of the KHP solution with a KOH solution of unknown concentration required 38.91 mL to reach a phenolphthalein end point. What is the concentration of the KOH solution

The concentration of KOH is  0.06137 M

Explanation:

Step 1: Data given

Molar mass of KHP = 204.22 g/mol

Mass of KHP = 0.4877 grams

Volume of water = 50 mL

Volume of KOH solution = 38.91 mL

Step 2: The balanced equation

C8H5KO4 + KOH ⇒ C8H4K2O4+ H2O

Step 3: Calculate number of moles of KHP

Moles = Mass / molar mass

Moles KHP = 0.4877 grams / 204.22 g/mol

Moles KHP = 0.002388 moles

Step 4: Calculate moles of KOH

For 1 mol KHP we need 1 mol KOH to produce 1 mol C8H4K2O4 and 1 mol H2O

For 0.002388 moles KHP we need 0.002388 moles KOH

Step 5: Calculate the concentration of KOH

Concentration = moles / volume

Concentration of KOH = 0.002388 moles / 0.03891 L

Concentration of KOH = 0.06137 M

The concentration of KOH is  0.06137 M

every chemical equation adheres to the law of conservation of mass, which states that matter cannot be created or destroyed. therefore, there must be the same number of atoms of each element on each side of a chemical equation.