SiO2\rightarrow H2SiO3 (axit siliccat)BaO \rightarrow Ba(OH)2 (bari hydroxit)
SO2 \rightarrow H2SO3 (axit sunfit)
SO3 \rightarrow H2SO4 (axit sunfuric)
N2O5\rightarrow HNO3 (axit nitric)
MgO \rightarrow Mg(OH)2 (magie hydroxit)
P2O5 \rightarrow H3PO4 (axit photphoric)
Al2O3 \rightarrow Al(OH)3 (nhôm hydroxit)
Fe2O3 \rightarrow Fe(OH)3 (Sắt hydroxit)