aeacfm - 11-10-2010 at 22:49
in our lab we measure sulfides in water spectrophotometry or by the method known as methylene blue method , but due to the highly interfering ions
present in the water we intended to use the other method iodometry titration.
after prepering the sample and performing titrations the volume of thiosulfate used was very high so that according to calculations the concentration
of sulfides was in minus sign ....lol!!!!
i dont know what can i do ?!!!!1
i supposed the following :
- may thiosulfate react with other component in the sample together with iodine.
- may be interfering ions still present (so i washed the sample many times - still the confusion present)
i dont know what is the problem can any body help?
ixxon2001 - 19-10-2010 at 19:54
may thiosulfate react with other component in the sample together with iodine
This is your likely problem. What ions might be present?
aeacfm - 26-10-2010 at 03:02
many
it is formation water
TDS of 200,000 ppm