How exactly does a typical acid(sulfuric, vitriolic) eat away at an object?

Answer 1

The acid attacks the bonds of the other reagent chemically and the reaction products are usually either mechanically weak or soluble in water. Let’s look at a piece of metal for example.

Say sulfuric acid attacks the metal. Sulfides will form. Sulfides are typically weak, mechanically. As a layer of sulfide builds up, it cannot support its own weight, and crumbles. Metals typically have a grain (like wood, only microscopic, formed as the metal cooled from the molten state.) The individual grains of metal within the mass of metal become individual grains of sulfide, and they fall apart. This is called erosion.

In addition to this, some sulfides may be soluble in water, and will actually go into solution. Eithr way, the object is dissolved and forms a sludge. For etching metals, heating and agitation of the solution will result in faster erosion.

20 DEC 06, 0155 hrs, GMT.