# How to estimate HCN content in a volatile mixture?

How can you accurately qualitatively and quantitatively determine the HCN in a volatile product from water?

• please, describe composition of the product in question at least in generic terms. Jul 29 '13 at 6:49
• This is a volatile gas produced from cassava leaf ditillate in water and shows colour test for cyanide but quantitative and confirmatory tests not obtained Jul 29 '13 at 7:00
• Did you test it with iron sulfate (forms prussian blue, intense blue pigment) ? Jul 29 '13 at 10:24
• the amount is too little to be determined by this method. I ma looking forward to some GC-MS or similar method Jul 30 '13 at 16:28

From a quick search of the literature, it seems that as you correctly thought, gas chromatography mass spectrography is a method that can be used to quantitate small amounts of cyanide in vapour.

While I am certainly no expert on this field or the precise method that you would use, this paper, which describes quantitation of cyanide and other chemicals in tobacco smoke may be of interest: A simple GC–MS technique for the analysis of vapor phase mainstream cigarette smoke

A specific $CN^-$ electrode will detect and measure from about 50 ppb of cyanide in water.