There are seven widely recognized strong acids in aqueous solution. Key list of strong acids:
- Hydrochloric acid (HCl)
- Hydrobromic acid (HBr)
- Hydroiodic acid (HI)
- Nitric acid (HNO3)
- Perchloric acid (HClO4)
- Chloric acid (HClO3)
- Sulfuric acid (H2SO4)
Notes:
- “Strong” refers to the degree of dissociation in water; these acids dissociate nearly completely.
- Some sources list the seven with sulfuric and perchloric acids included; others may emphasize the first six (HCl, HNO3, H2SO4, HBr, HI, HClO4) and treat HClO3 as a less commonly used example. The standard modern convention in many general chemistry texts is the seven above, with sulfuric acid counted as a strong acid due to its first dissociation being strong.
