Practice problem
Which ion pair will form an ionic compound in a 2 to 3 ratio?
Ca2+Ca^{2+}Ca2+; S2−S^{2-}S2−
Fe3+Fe^{3+}Fe3+; O2−O^{2-}O2−
Al3+Al^{3+}Al3+; Cl−Cl^{-}Cl−
Fe3+Fe^{3+}Fe3+; Be2+Be^{2+}Be2+
Type a concept, like “slope” or “photosynthesis”.
