A solution comprising a 70-to-30 ratio of this compound to pyridine typically makes up Olah’s reagent. This compound is often selected over sulfuric acid as the preferred catalyst during the alkylation of propene-rich petroleum feeds. A pentavalent antimony-containing compound is mixed (15[1])with this compound to form a solution with a pH below negative 31. Because one of its constituents can easily bind to serum calcium, exposure to this compound typically leads to hyperkalemia and (*) hypocalcemia. Spills of this compound (-5[1])are often cleaned using calcium gluconate gels. This compound has to be stored in chemically compatible containers made of polyethylene (10[1])or Teflon since it is strong enough to dissolve (10[1])metals and glass. For 10 points, name this corrosive binary acid consisting of the lightest element and the lightest halogen. ■END■