Table 4, Ionic Compounds and their Names
Formula of Ionic Compound
Cation and name of cation
Anion and name of anion
Name of ionic compound
NaCl
Na+ sodium
Cl- chloride
sodium chloride
AlPO4
Al3+ aluminum
PO43- phosphate
aluminum phosphate
CuSO4
Cu2+ copper (II)
SO42- sulfate
copper (II) sulfate
KNO3
K+ potassium
NO3- nitrate
potassium nitrate
Mg(OH)2
Mg2+ magnesium
OH- hydroxide
magnesium hydroxie
Fe2O3
Fe3+ iron (III)
O2- oxide
iron (III) oxide
AlCl3
Al3+ aluminum
Cl- chloride
aluminum chloride
Nomenclature of Ionic Compounds (using table 4 above)
1. Is the cation or the anion written first in the formula? Does this order change in the name?
2. Is the number of cations or anions in the formula communicated in the name of the compound? Why do you think it is unnecessary to do this?
3. The names of the cations are the same as the names of the elements for the main group metals in the table, but not for the cations of copper and iron. What's the significance of the Roman numeral in the names of the cations of copper and iron?
Analyzing Nomenclature Rules
1. Write a short description of the rules for naming covalent compounds based on the compounds explored in Table 3.
2. If the anion of oxygen is called oxide, and the anion of chlorine is called chloride, predict the name of the anions of sulfur, bromine and nitrogen. What would the charge be for each of these anions?
3. Write a short description of the rules for naming covalent compounds based on the compounds explored in Table 4.
4. Why is it not necessary to specify the charge of the cations of the alkali metals or the alkaline earth metals, but it is necessary to specify the charge of transition metal cations?
This has been a brief introduction to the systematic naming of covalent and ionic compounds. Only a small fraction of the many possible compounds have been presented here, but if you know the rules of nomenclature, and you know the formulas of the ions, you can name anything or interpret any name.