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What is the difference between Relative Formula Mass and Relative molecular mass Watch

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    I understand RFM is for ionic compounds, and RMM is for no ion compounds.
    I read my chemistry books they both seem to say you do the same thing but you use RFM for ions. Im confused by this. Why do we have to learn RFM if it helps you get no extra info since you get same answer from both formulas. -.- pls help if you can thanks.
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    (Original post by AngrySorcerer)
    I understand RFM is for ionic compounds, and RMM is for no ion compounds.
    I read my chemistry books they both seem to say you do the same thing but you use RFM for ions. Im confused by this. Why do we have to learn RFM if it helps you get no extra info since you get same answer from both formulas. -.- pls help if you can thanks.
    You make a decent point in that relative molecular and relative formula mass are used in the same way in calculations and so, in this sense, they are the same as one another.

    The differing names arise because RMM clearly applies only to compounds where molecules are involved. Ionic compounds do not consist of molecules and hence relative molecular mass is not applicable here, hence the need for the different name.
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    (Original post by MexicanKeith)
    You make a decent point in that relative molecular and relative formula mass are used in the same way in calculations and so, in this sense, they are the same as one another.

    The differing names arise because RMM clearly applies only to compounds where molecules are involved. Ionic compounds do not consist of molecules and hence relative molecular mass is not applicable here, hence the need for the different name.
    Oh ok thanks, i was just confused. Thanks for you help!
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    (Original post by AngrySorcerer)
    Oh ok thanks, i was just confused. Thanks for you help!
    I understand your confusion! The two values are, for most purposes, the same!
 
 
 
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