CDS /CDH

HOW DOES ONE TEST THE STRENGTH OF CDS/CDH, After them having been in the ref. over a month? I have about 150 ml of each, and neither seems to have lost any strength. The cd gas smell is still strong, and the color has not noticeably faded.
??????????

Thanks

Ken wrote: HOW DOES ONE TEST THE STRENGTH OF CDS/CDH, After them having been in the ref. over a month? I have about 150 ml of each, and neither seems to have lost any strength. The cd gas smell is still strong, and the color has not noticeably faded.
??????????

Thanks

The smell is not going to changed, but the concentration will. You place a 1 ml of the solution in 29 ml of distilled water and put the High conc. Strip Test . Should read about 100 ppm for the 3000 ppm solution.