Nitric acid is reported to react with silica primarily by dissolving it.
Based on reports, nitric acid plays a role in the dissolution of silica. The provided reference, citing Elmer and Nordberg (1958), explicitly states that nitric acid was reported to dissolve silica. This indicates that nitric acid helps in the process of breaking down and taking silica mineral into a solution.
The Dissolution Process
The interaction described involves nitric acid facilitating the dissolution of silica. This process is crucial as it makes the silica available for further reactions.
- Initial Step: Nitric acid interacts with the silica mineral (silicon dioxide, SiO₂) surface.
- Result: The silica is dissolved, meaning it is dispersed into the surrounding liquid medium, likely in some soluble form.
This initial dissolution step is presented as a preparatory action for subsequent reactions, as highlighted in the reference.
Subsequent Reactions
The reference also notes what happens after silica is dissolved by nitric acid:
"...thus, nitric acid helps dissolve the silica mineral. The dissolved silica in the presence of water reacts with sulfuric acid efficiently to form SSA."
This indicates that once nitric acid has dissolved the silica, the resulting dissolved silica, in the presence of water, can then efficiently react with sulfuric acid to form another substance referred to as SSA. While the reference does not explicitly name SSA, it describes its formation from dissolved silica and sulfuric acid.
Summary of Interaction
Here's a simple breakdown of the role of nitric acid with silica, according to the reference:
| Acid | Role in Interaction with Silica | Subsequent Reaction (if any) |
|---|---|---|
| Nitric Acid | Dissolves silica | Prepares silica for reaction with H₂SO₄ |
| Sulfuric Acid | Reacts with dissolved silica | Forms SSA |
In essence, nitric acid initiates the process by dissolving silica, making it amenable to further chemical transformations, specifically reacting with sulfuric acid.
