Question

Stimulus 2 A student sets up a titration for the standardization of NaOH using KHP (KHC3H404). The reaction proceeds as follows: NaOH(aq) + KHC9H404 (aq) --> KNaC9H404 (aq) + H20 (0 The student collects the following data: Initial Buret Reading NaOH 2.15 ml Final Buret Reading NaOH 20.83 mL What is the total volume of NaOH needed to neutralize the KHP? Answer in ml (don't type the unit) and with the correct number of significant figures Type your answer... 12 3 points so le If 0.3461 g of KHP were used in this experiment.what is the concentration (in molarity) of the NaOH solution? (Show all work) Round your answer to four places after the decimal. Type your answer.

Answer 1

a) We have to find the total volume of NaOH needed to neutralise KHP.

Initial reading of burette NaOH = 2.15 mL

Final reading of burette NaOH = 20.83 mL

Total reading = Final reading - Initial reading

= 20.83 - 2.15

= 18.68 mL (In 4 significant figures)

b) mass of KHP used = 0.3461 g

Molar mass of KHP = 204.2 g/mol

Number of moles = Given mass / molar mass

Number of moles of KHP =  0.3461g / 204.2 g/mol

= 0.001695 moles

The reaction between NaOH and KHP is in 1:1 stoichiometry. Therefore 0.001695 moles of KHP is must reacted with same number of moles od NaOH.

Number of moles of NaOH = 0.001695 moles

Volume of NaOH solution = 18.68 mL = (18.68/1000)L

= 0.01868 L

Molarity = no of moles / Volume in L

Molarity of NaOH =

0.001695moles 0.01868L

= 0.0907 M