query: What is the origin of the symbol Hg for mercury?
passage: Mercury (element)
Mercury is a chemical element with symbol Hg and atomic number 80. It is commonly known as quicksilver and was formerly named hydrargyrum (/haɪˈdrɑːrdʒərəm/ hy-DRAR-jər-əm).[4] A heavy, silvery d-block element, mercury is the only metallic element that is liquid at standard conditions for temperature and pressure; the only other element that is liquid under these conditions is bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature.
passage: George de Hevesy
In 1922 de Hevesy co-discovered (with Dirk Coster) the element hafnium (Hf) (Latin "Hafnia" for "Copenhagen", the home town of Niels Bohr). Mendeleev's 1869 periodic table arranged the chemical elements into a logical system, but a chemical element with 72 protons was missing. Hevesy determined to look for that element on the basis of Bohr's atomic model. The mineralogical museum of Norway and Greenland in Copenhagen furnished the material for the research. Characteristic X-ray spectra recordings made of the sample indicated that a new element was present. Later, in 1943, the discovery would earn Hevesy the Nobel Prize in Chemistry. The accepted account has been disputed by Mansel Davies and Eric Scerri who attribute the prediction that element 72 would be a transition element to the chemist Charles Bury.