RROR.
             · ACCURATE MEASUREMENTS HAVE LOW SYSTEMATIC ERROR AND, GENERALLY, LOW RANDOM ERROR AS WELL.
             Chapter 2: The Components of Matter.
             2.1 Elements, Compounds, and Mixtures: An atomic Overview
             · Pure Substance (PS)- Type of matter whose composition is Fixed.
             · Element - simplest type of matter, with unique physical and chemical properties. Consists of one kind of atom. (PS)
             · Molecule - independent structural unit consisting of two or more atoms that are chemically bound together. (PS)
             · Compound-Type of matter composed of two or more different elements that are chemically bound together. The elements are present in fixed parts by mass (fixed mass ratio) (PS)
             · Mixture- A group of two or more substances (elements and/or compounds) that are physically intermingled. The components of a mixture can vary in their mass ratio. (NOT a PS)
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