4.2 understand how to represent organic molecules using empirical forulae, molecular formulae, general formulae, structural formulae and displayed formulae

By Anonymous -
Molecular formula - 
It tells us the ratio of atoms present in the molecule. It tells us nothing about the structure. e.g.C4H10

 Empirical formula -
It represents the simplest whole number ratio of atoms of elements in a compound.

 Structural formula -
It shows how the atoms are arranged in the molecule. 

 Displayed formula -
It shows all the atoms and all the bonds in the molecule. the symbols for each atom are joined by straight lines. Each line represents a covalent bond

 General formula -
A chemical formula applicable to a series of compounds
Example:
The general formula of pentane is CnH2n+2
The molecular formula of pentane is C5H12
The structural formula will be CH3CH2CH2CH2CH3
The condensed structural formula will be CH2(CH2)3CH3

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