Chemistry / Unit 5: Chemical Names and Formulas
5.4 Naming Acids
Notes
An acid releases $\text{H}^+$ in water. Its name depends on the anion.
- Binary acids (H + one nonmetal): hydro- + root + -ic acid. HCl(aq) is hydrochloric acid; HBr(aq) is hydrobromic acid.
- Oxyacids with an "-ate" ion: root + -ic acid. $\text{HNO}_3$ is nitric acid; $\text{H}_2\text{SO}_4$ is sulfuric acid.
- Oxyacids with an "-ite" ion: root + -ous acid. $\text{HNO}_2$ is nitrous acid; $\text{H}_2\text{SO}_3$ is sulfurous acid.
- Memory trick: "I ate something ic-ky" and "-ite becomes -ous."
- Other common acids: $\text{H}_3\text{PO}_4$ phosphoric acid, $\text{H}_2\text{CO}_3$ carbonic acid, $\text{HC}_2\text{H}_3\text{O}_2$ acetic acid.
Practice
What is the name of HI(aq)?
HI has no oxygen, so it is a binary acid: hydro- + iod + -ic.
What is the name of $\text{H}_2\text{SO}_3$?
$\text{SO}_3^{2-}$ is sulfite, and -ite becomes -ous.
What is the formula of nitric acid?
"-ic" comes from nitrate, $\text{NO}_3^-$, so one H gives $\text{HNO}_3$.
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