General Chemistry placement test Study Guide Latest Update Rated A+

General C hemistry placement test Study Guide Latest U pdate Rated A+ molecule ✔✔two nonmetal atoms combined form a covalent comp ound called a diatomic molecules ✔✔H2,O2,F2 Matter ✔✔Anything that has mass and takes up space Element ✔✔A substance that cannot be broken down into simpler substances Compound ✔✔A pure substance made of two or more elements CHEMICALLY combined. Compound ✔✔Can be decomposed by chemically Mixture ✔✔A PHYSICAL blend of two or more components (aq) ✔✔aqueous mixture, a substance is dissolved in water homogeneous mixture ✔✔A mixture that is so evenly mixed that you can't see all of the different parts. Ex. Air, kool -aid heterogeneous mixture ✔✔A mixture in which different materials can be seen easily. Ex. soil, chocolate chip cookies filtration ✔✔process to separate a solid "precipitate" from a liquid sublimation ✔✔phase change from (s) --> (g) empirical formula ✔✔A formula showing the lowest whole number ratio of atoms in a compound. Can't be reduced. solid ✔✔A state of matter that has a definite shape and a definite volume liquid ✔✔A form of matter that flows, has constant volume, and takes th e shape of its container Bromine (Br) and Mercury (Hg) ✔✔only two liquids on the periodic table gas ✔✔A state of matter with no definite shape or volume gas ✔✔will uniformly and completely fill a container gases ✔✔physical property most all nonmetals and group 18 physical property ✔✔A characteristic of a substance that does not involve a chemical change. Ex. melting/boiling point, solubility, density, color, or hardness. properties ✔✔used to identify or re cognize matter (objects). chemical property ✔✔describes how matter reacts when it changes chemically into another substances. Ex. reactivity with acid, base or with air to rust, flammability, decomposition. physical/phase change ✔✔(s)-->(l)-->(g), diluti ng, crush, cut. Still same substance.