What is a strong acid?
what is a weak acid?
what is a weak acid?
Strong Acid A strong acid is an acid that is completely dissociated in an aqueous solution. It is a chemical species with a high capacity to lose a proton, H+. In water, a strong acid loses one proton, which is captured by water to form the hydronium ion:
HA(aq) + H2O → H3O+(aq) + A−(aq)
Diprotic and polyprotic acids may lose more than one proton, but the "strong acid" pKa value and reaction only refers to the loss of the first proton.
Strong acids have a small pH value
While there are many weak acids, there are few strong acids. The common strong acids include:
- HCl (hydrochloric acid)
- H2SO4 (sulfuric acid)
- HNO3 (nitric acid)
- HBr (hydrobromic acid)
- HClO4 (perchloric acid)
Weak Acid Definition A weak acid is an acid that is partially dissociated into its ions in an aqueous solution or water. In contrast, a strong acid fully dissociates into its ions in water.
weak acids have a higher pH value than strong acids.
Examples of Weak Acids Weak acids are much more common than strong acids.
They are found in daily life in vinegar (acetic acid) and lemon juice (citric acid), for example.
Common weak acids include:
Acid Formula acetic acid (ethanoic acid) CH3COOH formic acid HCOOH hydrocyanic acid HCN hydrofluoric acid HF hydrogen sulfide H2S trichloracetic acid CCl3COOH water (both weak acid and weak base) H2O
A strong acid is an acid that is completely dissociated in an aqueous solution. It is a chemical species with a high capacity to lose a proton, H+. In water, a strong acid loses one proton, which is captured by water to form the hydronium ion:
HA(aq) + H2O → H3O+(aq) + A−(aq)
Diprotic and polyprotic acids may lose more than one proton, but the "strong acid" pKa value and reaction only refers to the loss of the first proton.
Strong acids have a small pH value
While there are many weak acids, there are few strong acids. The common strong acids include:
- HCl (hydrochloric acid)
- H2SO4 (sulfuric acid)
- HNO3 (nitric acid)
- HBr (hydrobromic acid)
- HClO4 (perchloric acid)
A weak acid is an acid that is partially dissociated into its ions in an aqueous solution or water. In contrast, a strong acid fully dissociates into its ions in water.
weak acids have a higher pH value than strong acids.
Weak acids are much more common than strong acids.
They are found in daily life in vinegar (acetic acid) and lemon juice (citric acid), for example.
Common weak acids include:
| Acid | Formula |
| acetic acid (ethanoic acid) | CH3COOH |
| formic acid | HCOOH |
| hydrocyanic acid | HCN |
| hydrofluoric acid | HF |
| hydrogen sulfide | H2S |
| trichloracetic acid | CCl3COOH |
| water (both weak acid and weak base) | H2O |
