Question

Potassium hydrogen phthalate is a solid, monoprotic acid frequently used in the laboratory to standardize strong base solutions. It has the unwieldy formula of KHC₈H₄O₄. This is often written in shorthand notation as KHP.
What volume of a 0.201 M sodium hydroxide solution is needed to exactly neutralize 1.55grams of KHP ?
ANSWER: ____ mL sodium hydroxide

Potassium hydrogen phthalate is a solid, monoprotic acid frequently used in the laboratory to standardize strong base solutions. It has the unwieldy formula of KHC₈H₄O₄. This is often written in shorthand notation as KHP.
If 0.481 grams of KHP are needed to exactly neutralize 23.1 mL of a sodium hydroxide solution, what is the concentration of the base solution?
ANSWER: ____ M sodium hydroxide

Answer 1

The reaction between KHC8H4O4 (KHP)and NaOH goes like this

Hence 1 mol NaOH neutralises 1 mol of KHP.

Part 1

Amount of KHP to be neutralised = 1.55 g

Molar mass of KHP = 204.22 g/mol

Hence, number of moles of KHP to be neutralised is

Concentration of base NaOH being used = 0.201 M = 0.201 mol/L

Number of moles of NaOH needed to neutralise KHP = .

Hence, volume of 0.201 M that contains the required number of moles is

Hence, answer is 37.8 mL of NaOH.

Part 2

Volume of NaOH that is being neutralised = 23.1 mL

Amount of KHP being used = 0.481 g

Number of moles of KHP being used =

Hence, number of moles of NaOH present in 23.1 mL must be .

Hence, the concetration of NaOH solution is

Hence, the answer is 0.102 M NaOH.