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Grundstof

Et grundstof best�r udelukkende af atomer med samme atomnummer (antal protoner i kernen) � for eksempel jern, der udelukkende best�r af jernatomer Fe.

Vand derimod er et molekyle, der er sammensat af flere forskellige atomer - et iltatom O og to brintatomer H (det giver i alt H₂O), s� vand er ikke et grundstof.

Atomer af samme grundstof, der indeholder forskellige antal af neutroner, kaldes for grundstoffets isotoper.

Man kender 118 forskellige grundstoffer. Der er lavet en oversigt over grundstofferne, som kaldes det periodiske system.

Alle grundstoffer har deres eget, unikke, kemiske symbol, der er g�ldende over hele verden, uanset hvad grundstoffet hedder p� det enkelte sprog. Jern har symbolet Fe, ogs� p� dansk, og Natrium har symbolet Na, ogs� i de engelsksprogede lande, hvor Na hedder "sodium".

Table of contents

1 Se ogs� 2 Kilder/Henvisninger 3 Links

Se ogs�

• Grundstoffer efter atomnummer

Kilder/Henvisninger

• Hjemmesiden: http://www.naturligvis.u-net.dk/

Links

• 9 October 2003, PhysicsWeb: Darmstadt gets credit for new elements Citat: "...IUPAC has also officially approved a proposal from GSI that element 110 - which was also discovered at the German lab - should be known as darmstadtium (Ds)..."
• Number 672 #1, February 2, 2004, AIP: Element 115 Has Been Discovered Citat: "...The long lifetime observed for element 115 suggests that physicists might be getting closer to the "island of stability,"..."