[{"n": "Darmstadtium", "u": "/e/periodic-table-and-elements/darmstadtium/", "s": "The synthetic superheavy element named after a German city."}, {"n": "Dubnium", "u": "/e/periodic-table-and-elements/dubnium/", "s": "Synthetic element with shared discovery credit."}, {"n": "Einsteinium", "u": "/e/periodic-table-and-elements/einsteinium/", "s": "Synthetic element discovered in hydrogen bomb debris."}, {"n": "Extended periodic table", "u": "/e/periodic-table-and-elements/extended-periodic-table/", "s": "Hypothetical extension of the periodic table beyond element 118."}, {"n": "Fermium", "u": "/e/periodic-table-and-elements/fermium/", "s": "Synthetic actinide element discovered in hydrogen bomb fallout."}, {"n": "Flerovium", "u": "/e/periodic-table-and-elements/flerovium/", "s": "Synthetic superheavy element near the island of stability."}, {"n": "Group (periodic table)", "u": "/e/periodic-table-and-elements/group-periodic-table/", "s": "A column of elements with similar chemical properties."}, {"n": "Group 10 element", "u": "/e/periodic-table-and-elements/group-10-element/", "s": "Group of d-block transition metals including nickel, palladium, platinum, and darmstadtium."}, {"n": "Group 11 element", "u": "/e/periodic-table-and-elements/group-11-element/", "s": "Group of metals including copper, silver, gold, and roentgenium."}, {"n": "Group 12 element", "u": "/e/periodic-table-and-elements/group-12-element/", "s": "Group 12 elements: soft metals with full d-shells."}, {"n": "Group 3 element", "u": "/e/periodic-table-and-elements/group-3-element/", "s": "First transition metal group, disputed composition, key to rare-earth chemistry."}, {"n": "Group 4 element", "u": "/e/periodic-table-and-elements/group-4-element/", "s": "Group 4 transition metals: hard, corrosion-resistant, with a protective oxide layer."}, {"n": "Group 5 element", "u": "/e/periodic-table-and-elements/group-5-element/", "s": "Group 5 elements are refractory transition metals with high melting points."}, {"n": "Group 6 element", "u": "/e/periodic-table-and-elements/group-6-element/", "s": "Group 6 transition metals with high melting points and strategic uses."}, {"n": "Group 7 element", "u": "/e/periodic-table-and-elements/group-7-element/", "s": "Group 7 transition metals with +7 oxidation state trends."}, {"n": "Group 8 element", "u": "/e/periodic-table-and-elements/group-8-element/", "s": "Group 8: iron, ruthenium, osmium, and hassium."}, {"n": "Group 9 element", "u": "/e/periodic-table-and-elements/group-9-element/", "s": "Rare transition metals including cobalt, rhodium, iridium, and meitnerium."}, {"n": "Hassium", "u": "/e/periodic-table-and-elements/hassium/", "s": "Synthetic superheavy element discovered via cold fusion."}, {"n": "Lawrencium", "u": "/e/periodic-table-and-elements/lawrencium/", "s": "Synthetic actinide element named after cyclotron inventor Ernest Lawrence."}, {"n": "Livermorium", "u": "/e/periodic-table-and-elements/livermorium/", "s": "Synthetic superheavy element, named after Lawrence Livermore National Laboratory."}, {"n": "Lutetium", "u": "/e/periodic-table-and-elements/lutetium/", "s": "A rare earth element discovered amid priority disputes."}, {"n": "Tennessine", "u": "/e/periodic-table-and-elements/tennessine/", "s": "Synthetic element 117, discovered by Russian–American collaboration."}, {"n": "Technetium", "u": "/e/periodic-table-and-elements/technetium/", "s": "First predominantly artificial element, used in nuclear medicine."}, {"n": "Superheavy element", "u": "/e/periodic-table-and-elements/superheavy-element/", "s": "Synthetic radioactive elements beyond atomic number 103."}, {"n": "Seaborgium", "u": "/e/periodic-table-and-elements/seaborgium/", "s": "Synthetic element named after Glenn T. Seaborg."}, {"n": "Rutherfordium", "u": "/e/periodic-table-and-elements/rutherfordium/", "s": "Synthetic element named after physicist Ernest Rutherford."}, {"n": "Roentgenium", "u": "/e/periodic-table-and-elements/roentgenium/", "s": "Synthetic element named after the discoverer of X-rays."}, {"n": "Promethium", "u": "/e/periodic-table-and-elements/promethium/", "s": "A rare, radioactive lanthanide with no stable isotopes."}, {"n": "Plutonium", "u": "/e/periodic-table-and-elements/plutonium/", "s": "A radioactive actinide metal used in nuclear weapons and power."}, {"n": "Oganesson", "u": "/e/periodic-table-and-elements/oganesson/", "s": "Synthetic element with the highest atomic number known."}, {"n": "Nobelium", "u": "/e/periodic-table-and-elements/nobelium/", "s": "Synthetic actinide element named after Alfred Nobel."}, {"n": "Nihonium", "u": "/e/periodic-table-and-elements/nihonium/", "s": "Synthetic, radioactive element in group 13."}, {"n": "Neptunium", "u": "/e/periodic-table-and-elements/neptunium/", "s": "First transuranic element, radioactive and used in spacecraft power."}, {"n": "Mendelevium", "u": "/e/periodic-table-and-elements/mendelevium/", "s": "Synthetic actinide element first produced one atom at a time."}, {"n": "Curium", "u": "/e/periodic-table-and-elements/curium/", "s": "Synthetic radioactive element named after Marie and Pierre Curie."}, {"n": "Copernicium", "u": "/e/periodic-table-and-elements/copernicium/", "s": "A synthetic, highly radioactive element named after Nicolaus Copernicus."}, {"n": "Californium", "u": "/e/periodic-table-and-elements/californium/", "s": "A synthetic element used as a neutron source for reactors and medicine."}]