I think it is Mercury but im not sure if they still can use it. your going to have to double check
Mercury is a liquid metal used in thermometers. However, it becomes a solid at -37.9 F and it can cause mercury poisoning if ingested or inhaled. Therefore, most theremometers use ethyl-alcohol or a plastic strip covered with liquid crystals (called a liquid crystal thermometer).
Mercury!
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Mercury (Hg)
Mercury.
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Mercury.
Mercury, Hg
Mercury
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