Mercuric amidosulphonate

KH(S03N)2Hg(Hg.0H)2,H20, is obtained. Complete saturation with carbon dioxide under press, gives finally the free acid, (HS03.N)2Hg,0H)2. Sodium mercuric amidosulphonate, NHg.S03Na, is prepared similarly to the potassium salt it forms radiating clusters, or often felted masses, of slender, colourless needles. It differs from the potassium salt in that it is soluble in water on heating, whereas the addition of alkali is necessary to dissolve readily the former salt. 

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