Description: La matière est tout ce qui occupe de l'espace et possède une masse. Les états de la matière les plus connus sont: l'état solide, l'état liquide, l'état gazeux et l'état plasma. Le chauffage ou le refroidissement d'une substance fait passer son état de matière d'une forme à une autre. La quantité de matière est mesurée en unités de masse, par exemple en kg.

Term and definition status: The original definition of this term in English have been approved by a research astronomer and a teacher
The translation of this term and its definition is still awaiting approval

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