01:160:161 Study Guide - Final Guide: Atomic Number, Ionic Bonding, Covalent Bond
Document Summary
Element: the simplest type of substance with unique physical and chemical properties. Molecule: a structure that consists of two or more atoms. Chemically bound together and behaves as an independent unit. Compound: a substance composed of two or more elements, which are chemically combined. Mixture: a group of two or more elements and/or compounds that are, physically intermingled. Heterogeneous mixture: have one or more visible boundaries between the compound. Homogenous mixture: has no visible boundary, because the components are mixed as individual atoms, ions and molecules. *solutions exist in three phrases although we normally think of solutions are liquids. The 3 laws in section 2. 2: law of constant compositions (definite proportions): all samples of a compound have the same proportion by mass of the elements present. -example: water always has 89% oxygen, and 11% hydrogen: law of multiple proportions: involves two or more compounds that are composed of the same elements.
