ITEC Beauty Specialist – Skincare and Eye Treatments Practice Test

When different elements bond to form a compound, the smallest unit that still carries the properties of that compound is a molecule. A molecule is a group of two or more atoms held together by chemical bonds, and it represents the fundamental unit of many compounds, especially covalent ones. An atom is the basic unit of an element, not of a compound. An element is a pure substance consisting of one type of atom. An ion is a charged particle; while compounds can contain ions, the smallest repeating unit in an ionic solid is usually described as a formula unit rather than a molecule. Therefore, the smallest unit of a compound is best described as a molecule.