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Ammonium paratungstate (or APT) is a white crystalline salt of ammonium and tungsten, with the chemical formula (NH4)10(H2W12O42).4H2O.Ammonium paratungstate is produced by separating tungsten from its more.
A 2265 (OTTO) Ammonium paratungstate 99% Cas 11120-25-5 - used, refluxing the ammonia solution is advisable to speed up the dissolution of the oxide.