1) the simplest form of matter that has a unique set of properties. a) biology b) astronomy c) geology d) element 2) a group of electrochemical cells combined together as a source of direct electric current at a constant voltage. a) cluster b) trains c) polymers d) batteries 3) the substance that is present at the end of a chemical reaction. a) reactant b) product c) chemical reaction d) titration 4) state of matter that has a fixed volume but not a fixed shape. a) liquid b) soid c) gas d) plasma 5) a solid substance in which the particles are arranged in an orderly, repeating, three-dimensional pattern. a) crystal b) solid c) liquid d) vapor 6) the ability to do work. a) light b) work c) energy d) electricity 7) an organic compound that is made up of only carbon and hydrogen. a) hydrocarbons b) proteins c) nucleic acids d) halogens 8) a measure of the force acting on an object by gravity. a) light b) weight c) volume d) distance

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