Halides and pseudohalides with silver nitrate

Chemicals needed

distilled water

potassium bromide GSGESUND.gif (476 Byte) Xi

potassium chloride

potassium cyanate GSGESUND.gif (476 Byte) Xn     R 22    S 24/25

potassium iodide

potassium thiocyanate GSGESUND.gif (476 Byte) Xn     R 20/21/22-30    S 13

silver nitrate solution, diluted  GSGESUND.gif (476 Byte) Xi  GSUMWELT.gif (758 Byte)  N    R 34-50/53     S(1/2)-26-45-60-61

Instead of potassium salts one can use the corresponding sodium salt. If not all salts are available the experiment can be accordingly adjusted.

Production of silver nitrate solution

Equipment needed

test tube rack
for each salt one test tube

Test procedure


One disposes of the suspensions as silver-containing waste. If one does not collect this seperately, then as heavy metal waste, it is not to be discharged into the drainage.


The halides and pseudohalides of silver are insolube and precipitate. In weighing the deposits, one can also determine quantatively the halides/pseudohalides or silver ions.


DSCN0042.JPG (220058 Byte)

Precipitation of halides and pseudohalides. From left to right: chloride, bromide, iodide, cyanate, thiocyanate.


The experiment is based on an experiment from the school class.

Concerning the precipitation of cyanide: XII.2.1, "Cyanidnachweis als AgCN", S. 141, [3]