Gutzeit’s test

Gutzeit s test a brown stain is produced which is soluble in 80% alcohol, provided the concentration of antimony is not too high. 

Estimation Gravimetrically as Sulphide as Magnesium Pyroarsenate—Volu-metrically by Iodometric Methods with Potassium Bromate, etc.—The Marsh Test—The Gutzeit Test—Fleitmann s Test—Colorimetric Methods— Microohemioal Methods—Determination of Arsenic in Gases. 

Fleitmann s test this test depends upon the fact that nascent hydrogen generated in alkaline solution, e.g. from aluminium or zinc and sodium hydroxide solution, reduces arsenic(III) compounds to arsine, but does not affect antimony compounds. A method of distinguishing arsenic and antimony compounds is thus provided. Arsenates must first be reduced to the tervalent state before applying the test. The modus operandi is as for the Gutzeit test, except that zinc or aluminium and sodium hydroxide solution... 

In the opinion of the Analytical Methods Committee of the S,A,C. the molybdenum-blue method is considered to have inherent advantages over the Gutzeit method, which may be regarded as an estimation rather than a determination, since it depends on the evaluation of the intensity of a stain on a test-paper and the judgments of individual analysts may differ slightly. Nevertheless, within this limitation and provided that the details of the method are strictly observed, the Gutzeit method is adequate in many circumstances, particularly when it is necessary to ascertain whether or not an arsenic content exceeds a certain limit. It is also less intricate and time-consuming than the molybdenum-blue method. 

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