nickel

Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile. Pure nickel shows a significant chemical activity that can be observed when nickel is powdered to maximize the exposed surface area on which reactions can occur, but larger pieces of the metal are slow to react with air at ambient conditions due to the formation of a protective oxide surface. Even then, nickel is reactive enough with oxygen that native nickel is rarely found on Earth's surface, being mostly confined to the interiors of larger nickel–iron meteorites that were protected from oxidation during their time in space. On Earth, such native nickel is found in combination with iron, a reflection of those elements' origin as major end products of supernova nucleosynthesis. An iron–nickel mixture is thought to compose Earth's inner core.

Nickel ist ein chemisches Element mit dem Elementsymbol Ni und der Ordnungszahl 28. Es zählt zu den Übergangsmetallen, im Periodensystem steht es nach der älteren Zählweise in der 8. Nebengruppe oder Eisen-Platin-Gruppe, nach der neueren in der Gruppe 10 oder Nickelgruppe.

Nikkel is een scheikundig element met symbool Ni en atoomnummer 28. Het is een zilverwit/grijs overgangsmetaal.

Le nickel est un élément chimique, de symbole Ni et de numéro atomique 28. Longtemps confondu avec l'argent ou le cuivre, il est aujourd'hui utilisé pour la confection de monnaie et en alliage dans l'industrie.