Nitric acid: Characteristics
Strength, colour and chloride: what buyers check
What this tab covers The physical and chemical properties that set its grade, price and uses, with the commercial grades and the standards that define them.Commercial value depends on strength and purity. Fertiliser plants use weak acid on site. Nitration and electronics users need strong, low-chloride, low-metal grades. Colour (dissolved NO2) and iron indicate quality.
Properties that matter commercially
| Property | Value / specification | Why it matters | Source |
|---|---|---|---|
| Concentration | weak acid 55-68%; azeotrope about 68%; concentrated 98-99% | Sets use and whether extra concentration is needed | KBR; indicative |
| Density | about 1.41 g/cm3 at 68%; 1.51 g/cm3 at 99% (indicative) | Tank and pump design | Physical data (indicative) |
| Dissolved NOx | bleached acid typically under about 0.1% as NO2 (indicative) | Colour and stability for nitrations | Industry specifications (indicative) |
| Chloride and metals | electronic grades at parts per billion (indicative) | Wafer cleaning and etching | Industry specifications (indicative) |
Commercial grades
- Weak acid (55-68%) for AN
- Concentrated (98%+) for nitrations and explosives
- Electronic grade for semiconductors
- Reagent grade