What is iron III chloride

Ferric chloride FeCl3 
dark ones, green in supervision,
red when viewed through,
hexagonal leaves
Dirty yellowish pieces
molar mass 162.204 g / mol
(Hexahydrate 270.295 g / mol)
AGW not specified
density 2.90 g / cm3   
(Hexahydrate 1.82 g / cm3
Melting point +307.6 ° C
boiling point approx. +316 ° C
Water solubility(Hexahydrate)
100g H2O dissolve 91.94 g at 20 ° C

GHS 05
GHS 07
Hazard classes + category  
Corrosive to metals 1 (hexahydrate)
Acute toxicity oral 4
Irritant effect on the skin 2
Serious eye damage 1
HP rates (see also note)      
H 290 (hexahydrate), 302, 315, 318 P 264.1, 280.1-3, 301 + 312 + 330, 302 + 352, 305 + 351 + 338 + 310
disposal G 4
print a labelGerman nameEnglish name
CAS 7705-08-0 
CAS 10025-77-1
Ferric chloride
Iron (III) chloride hexahydrate *
Iron (III) chloride
Iron (III) chloride hexahydrate
*) Preferred for school, the bottle shown shows the hexahydrate.
The yellowish pieces of the hexahydrate, which smell slightly of hydrochloric acid, are highly hygroscopic and attract water in the air, so that they dissolve into a dark brown liquid. But they also dissolve in acetone, ethyl alcohol and diethyl ether.

The iron (III) chloride hexahydrate for etching is obtained in this form

If you add potassium hexacyanoferrate (II) to an iron (III) chloride solution, a deep blue precipitate of the pigment Prussian blue is produced. Anhydrous ferric chloride forms dark, green leaves when viewed from above, which melt at +307.6 ° C and at the same time partially sublime.
Brown, anhydrous iron chloride is obtained in the laboratory from the reaction of iron wool and chlorine. The iron chloride containing water of crystallization can also be produced by dissolving iron powder in hydrochloric acid and then introducing chlorine, the iron (II) chloride initially formed being FeCl passes into iron (III) chloride, which can be obtained by evaporating the solution. For technical production, chlorine is passed over scrap iron at around 650 ° C.
Iron (III) chloride is required as a chemical reagent in the laboratory. It is used as an oxidizing agent and pickling agent in textile printing. In water treatment it is used to precipitate and flocculate impurities, in medicine as a hemostatic agent (astringent), in copper gravure to etch metals and in electronics to etch circuit boards. The chemical industry needs ferric chloride in the production of dyes such as aniline black.
Experiment with Berlin blue