Answers

2014-05-12T19:56:10+05:30
Firstly use the pt to determine the atomic mass of each element inthe molecule 
then multiply each element atomic mass by the no. of atoms of that element in molecule ,this no is represented by subscript next to the element symbol in molecular formula .

then add these value together for each different atom in molecule 
the total will be the molecular mass
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2014-05-12T21:23:30+05:30
There is a ppt attached below which helps to find the molecular mass.
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