A. adding concentrated hydrochloric acid to solid manganese (IV) oxide
B. adding concentrated tetraoxosulphate (VI) acid to solid sodium chloride
C. dropping concentrated hydrochloric acid onto potassium tetraoxomanganate (VI) crystals
D. adding concentrated tetraoxosulphate (VI) acid to hydrochloric acid
Correct Answer:
Option A – adding concentrated hydrochloric acid to solid manganese (IV) oxide

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