Lesson 2: Element Names and Symbols

Symbols for Atoms

Dalton used symbols to represent his atoms. However, he did not use the same symbols that we use. He used circles with markings to represent the various individual atoms. He used circles with dots, lines, crosses and shading in them. When he ran out of marks he put letters in the circles to represent the elements. Each different symbol represented a different kind of atom--the atom of a different element. (See Ex. 5 in your workbook.)

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About ten years later, in Sweden, Berzelius suggested just using letters to represent atoms of each element and also to represent the elements in general. These are the symbols that we use today. Because we use the symbols in two different ways, you need to pay attention to the context in which a symbol for an element is used. Realize that sometimes it just represents the element and sometimes it represents an atom of the element.

Names of Elements

Some elements have been known since ancient times, even though they may not have been known to be elements at that time. They were known prior to and during the time that our various cultures and languages developed. Consequently some of these elements have names that are different in each culture or each language. Gold is a good example. Probably every culture has a name for the element gold, just as every culture would have its own name for the compound water and its own name for the sun. So that we might have just one symbol for each element, Berzelius based the symbol on the Latin name for each element.

In the other parts of this section you will be introduced to the

symbols used for the elements in a way that will hopefully make them a little easier for you to remember (or at least understand why some of them are so different than the names we use for those elements)

and also to the

chemical names for compounds so that you will be able to use them to determine what elements are contained in them.

Symbols for Elements | Chemical Names for Compounds

Symbols for Elements

Some symbols should make sense to you immediately--such as C for carbon, O for oxygen and S for sulfur. This is because the English name is very similar to the Latin name for these elements. Some of the others may be quite baffling--such as Na for sodium, K for potassium, Fe for iron, Au for gold, and Ag for silver. This is because the English and Latin names for these elements are quite different.

C	Na	Au
O	K	Ag
S	Fe

Some of the elements have a single letter for a symbol. These are generally the very common ones such as oxygen, or carbon, or they might be the only elements that start with that particular letter. All of the symbols that are a single letter use an upper case letter. (C not c; O not o; etc.)

Most of the elements have double letter symbols, and you have to make sure that you use an upper case for the first letter and a lower case for the second letter. That second letter is usually the first non-common letter between elements that have names starting with the same letter. For example, chromium and chlorine both start with "C" and so does the symbol. They both have "h" for the second letter but the third letter is different--it's "l" for chlorine, "r" for chromium--and thus the symbols for those two elements are Cl for chlorine and Cr for chromium.

Over the years chemists not only named and symbolized the elements, they also discovered new ones and made a great many observations and measurements of the elements. They observed similarities and patterns among the pure elements which cried out for someone to arrange them in some sort of organizational scheme. This was done and the result, after a number of modifications, is the modern periodic table of the elements. (Note: a few of the symbols may change as scientists reach agreement on the most recent elements.) We will have much more to say about the periodic table and its strange structure later in the course. You will find that it has a lot to do with the ways that elements combine with one another to form compounds.

You will need to become very familiar with the names and symbols for quite a few of the elements with which we work. You won't be responsible for all hundred-plus of them but rather just for three dozen that are listed in the objectives for this lesson. As the course progresses, remember that we will use symbols to represent individual atoms of the elements and as abbreviations for the names of the elements.

You will need to memorize the symbols and the names for these three dozen elements. There are a variety of ways of going about memorizing things. Use whichever methods work best for you.

Ag	Al	Ar	Au
silver	aluminum	argon	gold
B	Ba	Be	Br
boron	barium	beryllium	bromine
C	Ca	Cl	Co
carbon	calcium	chlorine	cobalt
Cr	Cu	F	Fe
chromium	copper	fluorine	iron
H	He	Hg	I
hydrogen	helium	mercury	iodine
K	Li	Mg	Mn
potassium	lithium	magnesium	manganese
N	Na	Ne	Ni
nitrogen	sodium	neon	nickel
O	P	Pb	S
oxygen	phosphorus	lead	sulfur
Si	Sn	Ti	Zn
silicon	tin	titanium	zinc

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Chemical Names for Compounds

We will spend more time later in this course working with the intricacies of chemical names. But there are a couple important things you should learn now. One is the reason for having a systematic method for naming chemical compounds. The other is identifying the elements contained in compounds, which is the first step in determining the formula and composition of compounds.

As chemists learned more and more about the composition of simple compounds, it became important to develop a system for naming these compounds in a way that showed their elemental composition. Common and descriptive names like salt, cinnabar, laughing gas, and blue vitriol tell us nothing about what is in a compound. Chemical names like sodium chloride, magnesium oxide, mercuric sulfide, nitrous oxide and cupric sulfate do a better job of conveying information about what elements are contained in a compound.

Common name	Chemical name	Elements contained
salt	sodium chloride	Na	Cl
magnesia	magnesium oxide	Mg	O
cinnabar	mercuric sulfide	Hg	S
laughing gas	nitrous oxide	N	O
blue vitriol	cupric sulfate	Cu	S	O

Here are some simple guidelines of what to look for in chemical names. (These compounds are also listed in Example 6 in your workbook.)

Generally when two elements combine, the name of the compound contains the names of both elements with the ending on the second element changed to "-ide."

Simple names of compounds with two elements
Name of compound	Elements contained
sodium chloride	sodium and chlorine

When the elements can form two compounds, the ending on the first element is changed to indicate how much of the second element it has combined with. The "-ic" ending indicates that the first element has combined with a large amount of the second element. The "-ous" ending indicates that the first element has combined with a small amount of the second element. The terms "large" and "small" are, of course, relative and they are related to the ratios in the Law of Simple Multiple Proportions.

Latin endings in names of compounds

Name of compound

Elements contained

mercuric sulfide	mercury with more sulfur
mercurous sufide	mercury with less sulfur

nitric oxide	nitrogen with more oxygen
nitrous oxide	nitrogen with less oxygen

Sometimes you will see a Roman numeral in parentheses attached to the end of the first element. These are Stock names and the Roman numeral tells us about the condition (charge or oxidation state) of the element it follows. We will have to deal with that when we talk about how atoms bond to one another later in this course.

Roman numerals in names of compounds
iron(III) oxide	iron (in a +3 state) with oxygen
iron(II) oxide	iron (in a +2 state) with oxygen

When an "-ate" ending is found in a name, it indicates that oxygen has combined with the other two elements.

Compound names with -ate endings
cupric sulfate	copper with sulfur and oxygen

Sometimes names will contain prefixes. The prefix is used to indicate the relative amounts of each element expressed in a way that I will soon discuss. For the moment, let's just leave it at the understanding that carbon dioxide contains both carbon and oxygen. In time you will learn which types of compounds have prefixes in their names and which do not.

Names containing prefixes
carbon dioxide	1 carbon with 2 oxygens