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EMPIRICAL FORMULA

EMPIRICAL FORMULA 
A formula which shows the simplest whole number ratio between the atoms present in a compound is called empirical formula.
Examples: H2O for water, CH for benzene (C6H6).
Steps to determine empirical formula:
Empirical formula of a compound can be calculated by the following the steps:
(i)   Determination of the percentage composition of each element.
(ii)  Finding the number of gram atoms (mole) of each element. For this purpose divide the %age of an element by its relative atomic mass.
(iii) Determination of the atomic ratio of each element by dividing gram atoms or mole by the smallest number of moles.
(iv)  If the atomic ratio is in simple whole number, it gives the empirical formula, otherwise multiply with a suitable digit to get the whole number atomic ratio.

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