Question

Name Section/CRN EXPERIMENT 9 POTENTIOMETRIC DETERMINATION OF AN EQUILIBRIUM CONSTANT PRE-LABORATORY QUESTIONS . The following preparatory questions should be answered before coming to b. are intended to introduce you to several ideas that are important to aspects of the experiment. You must turn in your work to your instructor before you allowed to begin the experiment. Potassium acid phthalate, KHP (KHC.H.O.), is a primary standard reagent used to determine exactly the concentration of a solution of base, such as NaOH, whose approximate concentration is known. KHP is a weak acid, and the equation for the neutralization of KHP by NaOH is Potassium sodium phthalate COOK COOK + + NaOH H2O -соон -COONa ΚΗΡ Potassium hydrogen phthalate 1. A Chem 1515 student dissolved 0.33 grams of KHP in 25.0 mL of water. He found out that it required 18.5 mL of NaOH to reach the endpoint of the titration. a. How many moles of the acid, KHP, were originally present before the addition of the base? b. How many moles of NaOH were required to neutralize the amount of KHP in Part a?

Answer 1

Given data: hydrogen phthalate neutralization with KHP) Potassium NaOH. of solution required in as me also 0.33 of KHP grams 18.5 me of NaoH present originally is a) The before no. of moles of KHP the addition of the base U moles of KHP = Given mass of KHP molar mass of kHP no. of we know, molar mass of KHP = 204.aa g/mole no. of mol of KHP = 0.33 = 0.001615. 204.22. =) mole. of KHP = 0.001615 no. of mol KHP is mono protic acid b) As we know For neutralization, no. of mole of KHP. no. of mole of NaOH. mole is = 0.001615 - no. of moles of NaoH required to netualized.