chem unit 1 test Flashcards
element
all atoms are the same
solid
atoms vibrate in one position (not free)
pure substance
made up of only one MATERIAL
what is the diff between an element and a pure substance?
all elements are pure substances
pure substance can be elements OR compounds
molecule
two+ atoms are chemically joined to make a molecule
compound
chemically combined 2 different atoms
liquid
molecules are relatively close and free; moving about randomly and slowly
gas
molecules are far apart and moving fast
mixture
diff types of atoms/molecules that are physically together but not chemically bonded
homo mixture
you can not physically see that it is NOT a mixture
hetero mixture
you can physically see that is IS a mixture
sig figs
the digits in a number that matter for showing how precise the measurement is
mass unit
g, mg, kg,
density unit
g/cm^3 or g/mL
volume unit
cm^3, m^3, mL,L