Group reagents

Anagnostopoulos found that the amino group reagents ketene, nitrous acid, formaldehyde, and phenyl isocyanate all inactivated bovine liver and kidney phosphatases 102). On the other hand, acetylation of chicken intestinal phosphatase with acetic anhydride gave an active product with optimum activity more alkaline than normal 103). The enzyme preparation was impure and acetylation only 70% complete... 

Functional Group Reagent Polarographically Active Derivative Active Polarographic Group... 

The group reagents used for the classification of most common cations are hydrochloric acid, hydrogen sulphide, ammonium sulphide, and ammonium carbonate. Classification is based on whether a cation reacts with these reagents by the formation of precipitates or not. It can therefore be said that classification of the most common cations is based on the differences of solubilities of their chlorides, sulphides, and carbonates. 

Group reagent hydrogen sulphide (gas or saturated aqueous solution). 

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