chemistry
study of matter and the changes it undergoes
matter
anything that has mass and takes up space
mass
the amount of matter in an object
weight
the force of gravity acting on an object's mass
pure substance
a substance with uniform, definite composition
elements
substance made of one kind of atom
compound
substance formed when elements chemically combine
mixture
two or more pure substances physically blended together
heterogenous mixture
does not have a uniform or definite composition
homogenous mixture
does not have a definite composition
atom
the smallest particle of an element to retain the properties of the element
electron
a negatively charged particle of negligible mass
nucleus
extremely dense, positively charged center of the atom
proton
a positively charged subatomic particle present in every atom.
neutron
an uncharged subatomic particle present in most atoms
isotopes
atoms of the same element with different numbers of protons
atomic number
the number of protons in an element's atoms
atomic mass
weighted average of all of the elements in an isotope
mass number
the total number of protons and neutrons in the nucleus
ion
a charged atom or group of atoms
cation
a positively charged atom or group of atoms
anion
a negatively charged atom or group of atoms