Part c titration of prepared acid solution 7 a sample

Part C – Titration of Prepared Acid Solution
7. A sample of the prepared HCl was
measured in a graduated cylinder and
transferred to a flask with phenolphthalein
indicator.
8. HCl sample was then titrated to endpoint
using the standardized NaOH solution.
HCl stock soln = 0.103 M
Part A #1 HCl (mL) NaOH (mL)
initial 0.00 0.15
final 26.12 27.60
Endpoint was a clear, very faint pink solution.
Part A #2 HCl (mL) NaOH (mL)
initial 0.48 0.40
final 25.55 27.16
Clear, very faint pink solution.
 Calculate how many mL of 6 M HCl you
need in order to make 250 mL of your assigned
concentration. Show your work to receive credit.
Part C HCl (mL) NaOH (mL)
initial
23.0
1.20
final 
Clear, very faint pink solution.

2
DATA ANALYSIS
Standardizing the NaOH Solution (Part A)
a. Determine how many liters (L) of stock HCl were used in titration #1.
b. Determine the number of moles of HCl in this volume of solution. (Hint: you will need to use
its concentration to calculate this.)
c. Determine the number of moles of NaOH . (Hint: you will need to know the chemical
relationship of HCl to NaOH; i.e. its stoichiometry.)
d. From the volume of NaOH used in titration #1, determine its molarity (M)
e. Repeat steps a-d for your second trial and average the two values for molarity of NaOH.
Determining the Titration Values of Prepared HCl (Part C)
f. Based on your assigned HCl concentration, determine the number of moles of HCl in the sample
used for titration. (Pay close attention to your units!)
g. Determine how many moles of NaOH were used to titrate this sample.
h. Determine what volume of NaOH this required, in liters (L)
i. Determine what the final reading on the buret must have been, in milliliters (mL), and enter it
into the blank box on the table for Part C.
.
.