physical-world
Longest-lived radioactive nuclide
Tellurium-128
physical-world
Most flammable metal
Potassium
physical-world
Least reactive metal
Gold
physical-world
Best thermal conductor (element)
Silver
physical-world
Most electronegative
Fluorine
physical-world
Most reactive with water
Cesium / Rubidium
physical-world
Least common naturally occurring (star-produced)
Technetium
physical-world
Most abundant in Earth’s crust
Oxygen
physical-world
Worst electrical conductor (solid)
Sulfur
physical-world
Most abundant metal in crust
Aluminium