relative isotopic mass
the mass of an isotope relative to 1/12th of the mass of an atom of carbon-12
relative atomic mass
weighted mean mass of an atom of an element relative to 1/12th of the mass of an atom of carbon-12.
binary compounds
contain 2 elements only
manganate (VII) ion
MnO4 -
nitrite ion
NO2 -
phosphate ion
PO4 3-
sulfate ion
SO4 2-