Carbonic acid is an important agent involved in rock and mineral dissolution. how is carbonic acid formed?

Carbonic acid a type of weak acid formed from the dissolving of carbon dioxide in water.

Explanation:

The chemical formula of carbonic acid is H2CO3. Its structure consists of a carboxyl group with two hydroxyl groups connected. As a weak acid, it partially ionizes, dissociates or rather, breaks apart, in a solution.

The "sub shells" are the orientations and shapes for your orbitals, going in order by Shells are a collection of subshells with the same principle quantum number, and subshells are a collection of orbitals with the same principle quantum number and angular momentum quantum number. Hope this helps :)