What is of, pertaining to, or designating, hypothetical sulphacid of tungsten (called also sulphowolframic acid), analogous to sulphuric acid, and known in its salts called?

sulphotungstic — Of, pertaining to, or designating, hypothetical sulphacid of tungsten (called also sulphowolframic acid), analogous to sulphuric acid, and known in its salts. (Webster's 1913.)

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