I did this lab today and i have to find the weight percent of chloride,
How can i solve this? using volhard methode.


Preparation of Solutions

2.   Prepare 100 mL of 0.15 M standard AgNO3 solution by accurately weighing out 2.54 g of AgNO3 to the nearest 0.1 mg. Transfer to a 100 mL volumetric flask and dilute to volume with deionized water. (Caution: Solid silver nitrate is toxic and corrosive. Contact with silver nitrate solutions results in the development of interesting black marks on the skin. Be careful to avoid skin contact.)

3.   Prepare 250 mL of 0.0375 M KSCN solution by weighing out 0.91 g of KSCN, transferring to a 250 mL volumetric flask, and diluting to volume with deionized water.

Standardization of KSCN Solution

4.   Combine thirty mL of deionized water and three mL of 6 M HNO3 into each of three 250 mL conical flasks. Pipet 10 mL of 0.15 M AgNO3 into each.
5.   Add 1 mL of ferric ion indicator and titrate with KSCN solution until the supernatant acquires a faint light brown colour which does not disappear on swirling the solution.




Analysis of Unknown

6.   Obtain an unknown from your instructor. This has been dried in an oven prior to the laboratory. If it is still hot, store it in a dessicator until it reaches room temperature.

7.   Accurately weigh out 0.5 to 0.6 g of your unknown and transfer to a 100 mL volumetric flask. Dilute to volume with deionized water.

8.   Into each of three 250 mL erlenmeyer flasks, pipet 10 mL of 0.15 M AgNO3 and 10 mL of your unknown solution. Add 10 mL of water and 3 mL of 6 M HNO3. Cover with a watchglass and heat the solutions on a hot plate or Bunsen burner until the supernatant is clear.

9.   Filter one of the solutions through a sintered glass crucible. Wash the precipitate, the flask, crucible, and crucible holder with small portions 0.01 M HNO3 (Prepare about 200 mL from 0.1 M HN03 stock solution.) To the vacuum flask, add 1 mL of ferric ion indicator, and titrate with KSCN solution until the filtrate just acquires a faint light brown colour that does not disappear on swirling. Be careful not to lose droplets in the suction arm of the flask. Repeat this process for the other solutions.

my end point for uknown was 13.67 ml and i I used 0.5277g of the uknown..

my endpoint for the KSCN titration was 39.02 ml and i sued 0.941g of KSCN
AgnO3 2.5116g