
The 2 in front of
in
is <u>Coefficient.</u>
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The
after
in the same equation is <u>sub </u><u>script</u><u>.</u>
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There are two atoms of
in 
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Hope you could understand.
If you have any query, feel free to ask.
The SAME number of molecules are in ANY “mole” of a compound or element. So, you only need to ... 24 g116 g/mol=0.207 moles of FeF3.