(a) The substances with high melting points may be (molwcular, non molecular , either molecular or non molecular) substance.
(b) Atomic mass can be measured by a(an) (ordinary, balance, spectrometer, mass spectrometer).
(c) A symbol represents (a molecule, an atom , a formula ) .
(d) The name of Fe2O3 is (iron (II) oxide, an atom , a formula).
