Chapter 2 Flashcards
Matter
anything with mass & takes up space
Pure substance
has fixed composition and definite (chemical & other) properties
Element
substance that can’t be broken down into simpler substances by chemical means: represented by symbol on PT
Atom
smallest unit of element that keeps element’s chemical properties
Molecule
smallest unit of substance that behaves like substance
Compound
substance made of atoms of different elements
Every molecule in compound
has 2 or more elements chemically combined
Mixture
combination of substances not chemically combined
Heterogeneous mixture
not evenly distributed and don’t easily mix/may be immiscible (won’t mix / stay mixed)
Homogeneous mixture
evenly distributed, will mix/stay mixed
Physical change
affects 1 or more physical properties of substance w/o changing substance’s identity
Chemical change
one or more substances are changed into new substances with different properties
Physical properties
color, mass, shape, melting/boiling point, magnetism, volume, odor. density
Chemical properties
flammability, reactivity
