Core
Reactions: Acid-base
Slide 9 of 42
Acid anhydrides of
some select acids
Many
oxides of non-metals when dissolved in water produce acids. The oxides of
non-metals, the starting materials for inorganic acids are referred to as acid anhydrides (anhydride = “without water”).
Acid
anhydrides produce acids (oxacids) when dissolved in water (hydrated).
Most oxacids have a corresponding acid anhydride. The following
equations show some selected acid anhydrides undergoing
hydration to produce their corresponding acid.
SO2 (g) + H2O (l) ® H2SO3 (aq)
SO3 (g) + H2O
(l) ® H2SO4 (aq)
N2O5 (g) + H2O (l) ® 2HNO3 (aq) N2O3 (g) + H2O (l) ® 2HNO2 (aq)
P2O5 (s) + 3H2O (l) ® 2H3PO4 (aq)
P2O3 (s) + 3H2O (l) ® 2H3PO3 (aq)
CO2 (g) + H2O (l) ® H2CO3 (aq)