SYMBOLS AND FORMULAE

SYMBOLS AND FORMULE
Introduction : 
    In order to represent the elements, instead of using full lengthy names, scientists use abbreviated names. These abbreviated names of the elements are known as symbols.As you denote '+' is a symbol to addition and '' is a symbol for division in mathematics similarly each element is denoted by a symbol in chemistry. Thus, symbol may be defined as the abbreviation used for the name of an element.
NOTE : The abbreviation used for the name of an element is more precisely known as chemical symbol of that element.
Definition of Symbol:
    A symbol is defined as an abbreviation or Short hand notation of full name of an element . Significance of a Symbol
    A symbol signifies the Qualitative and Quantitative measure of an element
Qualitative Significance : 
    Qualitatively symbol represents a specific element only and no two elements will have same symbol
    A symbol represents one atom of an Element
    For example "C" stands for carbon, Qualitatively it means that  symbol "C" signifies only carbon and no other element will have the symbol " C" and symbol "C" represents one atom of Carbon Qualitatively
Quantitative Significance :
    Quantitatively symbol represents atomic mass of an element
    For example "C" stands for carbon, Quantitatively symbol "C" signifies atomic mass of Carbon.
Rules of Assigning Symbols
    Symbols can be denoted by the single letter, two letters & three letters. The symbols of elements are generally either the first or the first two letters or the first and the third letters of the name of the element.
1) An element is represented with the first letter in capital of the english name of the element.
    For example, the symbols of the following elements are the first letter of the name of that element

2) When the names of two or more elements begins with the same initial letter, the letter followed by the next letter is used to represent the element.

It is important to note that the first letter of every chemical symbol is capital letter but, if the symbol consists of two letters, the second letter is not capital letter, thus 
Symbol for aluminium is Al and not AL 
Symbol for lead is Pb and not PB
Carelessness in writing symbols can lead to utter confusion.
For example,
    "Co" is cobalt whereas "CO" is carbon monoxide. Therefore, if a person uses symbol CO for cobalt, the one who read  symbol will take it as carbon monoxide which is a compound of carbon and oxygen.  
    Some symbols derived from the first and the third letters of the names of the elements.

3)There are certain symbols which seem to have no relationship to their names. The symbols of these elements are, in fact, derived from their latin names.

4)Elements named after scientists.

5)Some elements are named after planets.