Chapters 6.1-6.6

6.1Common and Systematic Names

   Chemical nomenclature is the system of names

used to identify compounds.

Common names are historically based and do not

represent any particular chemical composition.

Common names are still used for several

compounds because it is much easier  for

people to continue to refer to them as they were

in the past than to change.    Exp.:

                                               water,

                                               ammonia,

                                               & lime

There is a systematic method agreed to

internationally and used by chemists of all

countries to convey the same information.

This is the IUPAC or International Union

of Pure and Applied Chemists which was

devised by them.

6.2 Elements and Ions

   All atoms are composed of protons, neutrons,

and electrons. The number of protons in an

element define that particular element. An

uncharged atom contains the same number

of protons and electrons.

    A charged atom (ion) comes from the

addition or subtraction of one or more

electrons.          Exp:

Ions are most often formed when metals

combine with nonmetals. They are not

formed on their own.

6.3 Writing Formulas from Names of Compounds

   The formulas of compounds are derived from

the systematic application of the element symbols.

There are some rules that should be followed in

the process of naming compounds.

* 1. Write the formulas of the ions

   2. Combine the smallest numbers of positive

      (cation) and negative(anion) ions so that

      the total charge is equal to zero.

   3. Write the numbers as a subscript following

       the symbol to indicate the total number of

       those ions.

Try This !   Example: Aluminum fluoride

1. The ions in the example are Al³⁺ and F^1-

2. 1-Al³⁺and 3-F^1- will add up to zero

3. AlF₃ is the correct answer

Example: Calcium nitride

1. Ca²⁺ and N^3- are the ions

2. 3-Ca²⁺ and 2-N^3- will add up to zero

3. Ca₃N₂ is the correct answer

6.4 Binary Compounds

   The name of the chemical is composed of the

name of the metal followed by the name derived

from the nonmetallic element.

Exp.: NaCl    Na = sodium    /  Na¹⁺= sodium cation

                     Cl = chlorine  /   Cl^1-= chloride anion

Answer: Sodium chloride

The root is chlor and the suffix is -ide. This is the

way the name of the anion is formed.

The following table is a list of the common

monatomic anions formed from their elements

along with their corresponding names:

Binary Compounds with Metals /Forming Multiple Ions

Most of the metals in the periodic table can form more

than one type of ion corresponding to more than oxidation

state. The ions are differentiated from one another by

adding a roman numeral to the name of the ion. For

example: iron can form ions with either a +2 charge or

a +3 charge. These two are distinguised as follows: Iron

with +2 charge is called Iron (II) and iron with a +3 charge is

called Iron(III). In the older terminology these were called 

ferrous and ferric respectively.

The naming of the compound is similar to the naming

done for other ions.

Example1: Iron (III) chloride is FeCl₃

*Notice that the charges still balance out to zero.

Example2: Iron (II) phosphide is Fe₃P₂

6.5 Naming Compounds w/ Polyatomic Ions

   A polyatomic ion is an ion made up of two or more

element. Naming compounds containing polyatomic

ions it is necessary to recognize the common ions.

The compound CaSO₄ consists of two parts, the

cation (Ca²⁺ ) and the anion (SO₄^2-). The

polyatomic ions that contain oxygen often have the

suffix -ate or -ite. The ion with the -ate suffix

contains more oxygen than the one with the -ite.

Example: SO₄^2-  Sulfate

                 SO₃^2-   Sulfite

6.6Acids

    Acid formulas often begin with hydrogen. Compounds

of the inorganic type containing hydrogen, oxygen are

called oxy-acids.

Anions Table / Acids Comparison