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The Significance Of A Symbol

Chemistry is all about chemical elements and their reactions. Unique symbols denote these elements. But, who designates elements and why? Below is a detailed discussion on the symbol of an element and its significance.

In Chemistry, an element is the purest form of a substance. It consists of only atoms. Hence, by any means, elements can not be broken down further. The elements were classified and assigned a specific position in the modern periodic table depending on their physical and chemical properties. To be precise, the formation of the periodic table was led by the periodic recurrence of similar properties observed among different elements. 

Atomic number (Z) is one major factor determining an element’s position in the periodic table. All the elements are arranged according to an increasing atomic number. Also, these can be classified into metals, metalloids, and non-metals based on their properties and nature. Each element in the periodic table is represented by an abbreviation that designates elements. What is it?

What are the symbols that designate elements?

The abbreviations used in Chemistry to represent the chemical elements, functional groups and chemical compounds in a chemical reaction are known as chemical symbols. Usually, the symbol of an element consists of one or two Latin alphabets. The first letter is always written capital while writing symbols of any element, compound or functional group. 

Unlike most elements, few elements are assigned with a three-letter symbol. These are the temporary symbols given to the newly synthesised elements or are yet to be synthesised. Hassium is an example of this situation. With its atomic number as 108, Hassium was earlier named unniloctium, based on the digits of its atomic number. Therefore, Uno was the temporary symbol for Hassium or unniloctium. 

It is also noteworthy that no two elements have the same symbol. It means that every element has a unique symbol. If the first letters of two symbols are the same, there must be a second letter for differentiating between the two. For example, Carbon ( C ) and Copper (Cu) have their first letters as C, but copper has ‘u’ as a second letter. Thus, the two elements have unique symbols. 

Additional details represented by a chemical symbol

The symbol of an element represents an element. But, in addition to this, it can also represent additional details about the element. Information such as a particular isotope, ionisation or oxidation state of an element is represented by adding superscripts and subscripts to the designate elements symbol. The superscripts and subscripts added to the element’s symbol have the following meanings: 

  • The mass or nucleons numbers is added to a symbol on the left superscript position. It is crucial to define a specific isotope. To indicate a nuclear isomer, letters such as ‘m’ and ‘f’ get used. 
  • The atomic or the proton number is written in the left subscript position of the element’s symbol. 
  • The ionisation state or an excited state can also be represented in the right superscript position. But, this is only used when necessary. 
  • If the symbol represents a compound or molecule, the number of atoms is represented in the right subscript position. Here, it is crucial to note that if the number of atoms is one, this is omitted as it is implicitly understood. 
  • A radical can also be represented by putting a dot on the upper right side of the symbol. This is also preferred to be omitted unless a specific context requires it to be mentioned. 

Chemical symbols given to others

The symbols are not only limited to elements or compounds. Numerous functional groups and isotopes of some elements are also given unique symbols. 

  • Some functional groups are also given unique symbols to represent them. For example, Ph is the symbol for the phenyl group, and the methyl group is Me. 
  • Several isotopes are also given unique symbols. For example, the named isotopes of Hydrogen- Deuterium and Tritium are represented by symbols D and T. 

Significance of symbols

  • Symbols are considered significant as they represent the stoichiometric quantity of the element. They represent how many atoms of a particular element are being used or released in a chemical reaction. 
  • The symbol represents the definite mass of a specific element in a chemical reaction.
  • Writing full names of the compounds or elements in a complex chemical equation can be tedious and result in mistakes. It is where symbols help. Using abbreviations makes it easy to remember the names and write a chemical equation accurately. 
  • Symbols give a unique identity to every element and ensure that it will be identified as only the element or molecule it is representing when a symbol is seen. 

Conclusion

Symbols that designate elements represent their name and tell other information about it. A unique symbol denotes each element. It is also possible that some elements have their symbols derived from their ancient Greek, Latin, Arabic or German names. The significance of these symbols is undeniable in the subject of Chemistry. 

To be precise, the symbols were given to each element to ensure that they play a familiar role in representing an element even though they have different names in different languages. Hence, each of the discovered 118 elements has a unique symbol.

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