When nonmetallic oxides react with water, they typically produce acids. Here's why:

* Nonmetallic oxides are often referred to as acidic oxides.

* Water is a neutral molecule, but it can act as a base in certain reactions.

When a nonmetallic oxide reacts with water, the oxide molecules donate a proton (H+) to the water molecules, forming hydronium ions (H3O+), which is the characteristic of an acid.

Here are some examples:

* Carbon dioxide (CO2): CO2 + H2O -> H2CO3 (carbonic acid)

* Sulfur dioxide (SO2): SO2 + H2O -> H2SO3 (sulfurous acid)

* Nitrogen dioxide (NO2): NO2 + H2O -> HNO3 + HNO2 (nitric acid and nitrous acid)

Note: The reaction of nonmetallic oxides with water is often reversible, meaning the acid formed can decompose back into the oxide and water under certain conditions.