Multiple choice chemistry principles of metallurgy concentration of ore concentration of ores general principles of metallurgy In Bayer's process, the crushed ore is treated with ______ . hot concentrated caustic soda (NaOH) cold dilute caustic soda (NaOH) hot concentrated caustic potash (KOH) cold dilute caustic potash (KOH) Reveal answer Fill a bubble to check yourself A Correct answer Explanation Bayer's process is the industrial refining process to refine bauxite to produce alumina. In this process, the crushed ore is treated with hot concentrated caustic soda (NaOH).