Conductimetric Titration & Gravimetric Determination of BaSO4
Lab Report
NAME: Xiangyi Wu
PARTNER: Anchen Sun
SECTION: NY
TA: S.K. Sharma
DATE: 02/26/2015

INTRODUCTION
This experiment is to analyze a solution of Ba(OH)2 with unknown concentration in two ways, Conductimetric Titration and Gravimetric Determination.
PROCEDURE
Transfer 10ml Ba(OH)2 solution to a 100ml beaker with a 10ml graduated cylinder. Then add 30ml distilled water into 10ml Ba(OH)2 solution, using the 10ml graduated cylinder.
Connect Drop Counter to DIG/SONIC1 to the computer, switch conductivity probe to 0-20000 range, then start the Logger Pro.
Transfer 60ml of 0.100M H2SO4 into 250ml beaker.
Check the reagent reservoir, then rinse it by H2SO4 if it doesn't leak.
Fill the reagent reservoir with slightly more than 40ml H2SO4 solution.
Test the volume per drop and keep the dropping rate at one drop per second.
Place a magnetic bar in the beaker with BaSO4 solution, then turn on the switch of light and the stir.
Start to record the conductivity of the solution, keep dropping when reaching the lowest point and stop when the conductivity reaches 5000uS again. It appears a V-shape and then linear fit and adjust Y-axis scale.
Heat the beaker to nearly the boiling point and then cool it to the room temperature.
Weighed and record a filter crucible and then wet the filter disk with a milliliter of methanol.
Sit the crucible on the vacuum apparatus, filter the solution and get the crucible with precipitate into the drying oven for 15-20min, them weigh the crucible with BaSO4 solid.
EQUATION
Ba2+ + 2OH- + 2H+ + (SO4)2- ---- BaSO4(solid) + 2H2O
OBSERVATION