I. Hg (Mercury) - Distillation Distillation is a refining process used for volatile metals with low boiling points. Mercury is a liquid metal at room temperature and has a relatively low boiling point (356.7∘C), making it suitable for purification by distillation to separate it from nonvolatile impurities. This match is correct. II. Cu (Copper) - Poling Poling is a pyrometallurgical refining process used to remove small amounts of oxygen from molten copper (blister copper). In this process, green wood logs are stirred into the molten copper. The hydrocarbons in the wood act as reducing agents, converting cuprous oxide (Cu2O) to metallic copper. This match is correct. III. B (Boron) - Zone refining Zone refining is a purification technique used for producing extremely pure metals and metalloids, especially for semiconductor applications. It works on the principle that impurities are more soluble in the molten state than in the solid state. Boron is a metalloid, and ultra-pure boron is vital for certain applications. Zone refining is indeed a method used for the purification of boron, as well as silicon and germanium. This match is correct. IV. Ti (Titanium) - Liquation Liquation is a refining process suitable for metals with low melting points that can be separated from higher melting point impurities (e.g., tin, lead). Titanium, however, has a very high melting point (1668∘C). Its refining typically involves methods like the Kroll process (to produce titanium sponge) followed by electron beam melting or vacuum arc remelting for further purification. Liquation is not appropriate for titanium. This match is incorrect. Based on the evaluation, pairs I, II, and III are correctly matched.
