In the formula:
a) Separate from the salt
cation and anion
Deduces the charge of the anion (negative ion) from the
charge of the cation (positive ion)
b) Deduces the oxidation number of the
central atom, knowing that the oxygen has oxidation number -2
and hydrogen +1.
c) Recalls oxidation numbers of
central element, and writes the prefixes and suffixes.
The first word is the name of the metal, followed
immediately by the oxidation number between brackets and in Roman numbers. If
the oxidation number of the metal is invariable, it is not indicated. The second
word is the name of the anion with the prefixes hydrogen- or dihydrogen-.
In the name:
a) Write the symbol of the
cation with its electrical charge. Based on the prefixes and
suffixes deduces the number of oxidation central element involved in the anion:
b) Formulates the oxyacid of S+4
c) Deduces the anion from the acid. The anion has so many negative electrical charges as hydrogens
loses the acid.
Calculate the fewest ions of each type that you need so that the compound be
As in oxyacids we use two
nomenclatures: is the additive names and the stoichiometric names.
The additive names for anions:
are based on the structure of the anions, naming differently the oxygen that are
tied to the acid hydrogens (hydroxido), and the oxygen only united central
element (oxido). These names carry prefixes corresponding di-, tri-,
tetra- and so on. And are named in alphabetical order followed by the name of
the central atom finished in –ate, followed by the charge number, with a
minus sign, between brackets. (Ewens-Bassett's system)
The stoichiometric names for anions:
are formed by the word "hydrogen" with the prefix that shows us the
number of atoms of hydrogen and the word "oxido" with the
prefix that shows us the number of atoms of oxygen, followed by the central
atom finished in –ate, followed by the charge number, with a minus
sign, between brackets. (Ewens-Bassett's system)
The additive names
for salts: Write the name of the cation followed by the name of the
anion, with the charge ( Ewens-Bassett's system) in cantions having no fixed
The stoichiometric names
for salts: Write the name of the cation, with the prefixes di-,
tri-, tetra-, etc. we suggest repetition of the cation. Following the anion
without the charge, if necessary with a prefix, tris, tetrakis, pentakis,
hexakis, etc. tell us that the repetition of anion.
In Formulae you have an exercise to write the names of these substances
and to check your results. You also have the answer to the exercise.
In Names you have an exercise to write the formulae for these substances
and to check your results. You have to introduce the formulae without
subscripts, for example for water = H2O. You also have the answer to the