Unit 10 – Naming Acids
Acids are molecular compounds that release H+ when dissolved in water
Even though they are molecular, the compound can be viewed as hydrogen(s) with an
anion (negative ion).
Example: HCl has H1+ and the anion, Cl1If the anion does NOT contain oxygen:
the prefix “hydro” is added to the root name of the element
the suffix “ic” is added to the root name of the element
Examples: chemical formula
HCl
HCN
H2S
acid name
hydrochloric acid
hydrocyanic acid
hydrosulfuric acid
If the anion CONTAINS oxygen:
It is a polyatomic ion, and its name determines the suffix
If the anion name ends in “-ate”, the ending is changed to “-ic”
If the anion name ends in “-ite”, the ending is changed to “-ous”
Examples:
chemical formula
HClO3
H2SO4
H2SO3
anion name
chlorate
sulfate
sulfite
acid name
chloric acid
sulfuric acid
sulfurous acid
To write the chemical formula from the acid name:
Assume that hydrogen has a charge of 1+
Write the anion with its charge
Write the chemical formula so the charges add up to zero
Examples:
hydrochloric acid prefix of “hydro-“ means the anion has no oxygen,
“chlor” means chlorine
H1+ Cl1-
chemical formula is HCl
sulfuric acid no prefix means the anion has oxygen (polyatomic)
“-ic” means the anion ends in “-ate”  sulfate
H1+ SO42- chemical formula is H2SO4
nitrous acid no prefix means the anion has oxygen (polyatomic)
“-ous” means the anion ends in “-ite”  nitrite
H1+ NO21- chemical formula is HNO2
PRACTICE PROBLEMS: Solve on the left page
Write acid names: 1. HBrO3
2. H3PO4
3. HF
Write formulas: 4. hydrocyanic acid
5. nitric acid
6. perchloric acid