FORMULA OF A SUBSTANCE

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 FORMULA :-

Formula is the symbolic representation of the molecule of a substance. 

Ex :- Water is represented by H2 O, Sodium chloride is represented by NaCl etc. 

Formula can be classified into three types:-

i) Empirical / Simple formula

ii) Molecular formula

iii) Structural formula

Empirical formula 

In this type of formula, the ratio between the atoms of the various elements present in one molecule of the compound. 

OR

The simplest formula of the compound is called empirical formula. 

Ex :- Actual formula of glucose is C6 H12 O6  but its empirical formula is CH2 O (1:2:1). 

Molecular formula 

It is defined as the actual number of atoms of the various elements present in one molecule of the compound.

Ex :- Molecular formula of glucose is C6 H12 O6  . It is made up of 6 atoms of'C' , 12 atoms of 'H' and 6 atoms of 'O'.

Structural formula 

In this type of formula, the atoms of various elements are linked together in a molecule. 

Ex :- The structural formula of CH4  is 










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