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    Why is the formula for lithium bromide LiBr.

    I understand that there Lithium has a 1+ charge and Bromine has a 1- charge. But isn't bromine a diatomic molecule - so shouldn't the formula be 2LiBr?

    Please help!
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    Hi everyone!

    Why is the formula for lithium bromide LiBr.

    I understand that there Lithium has a 1+ charge and Bromine has a 1- charge. But isn't bromine a diatomic molecule - so shouldn't the formula be 2LiBr?

    Please help! :confused:
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    (Original post by park1996)
    Hi everyone!

    Why is the formula for lithium bromide LiBr.

    I understand that there Lithium has a 1+ charge and Bromine has a 1- charge. But isn't bromine a diatomic molecule - so shouldn't the formula be 2LiBr?

    Please help! :confused:
    Diatomic just means that is is found as the dimer X2 in it's natural form. This does not effect the compounds it forms. Br typically only forms one covalent bond and is diatomic in its elemental form. Equally oxygen and nitrogen are diatomic but form 2 and 3 covalent bonds respectively.

    LiBr is a giant ionic lattice so placing a number in-front of the empirical formula is pointelss. In reality a crystal of LiBr would actually be somewhere of the order (10^24)LiBr
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    The formula is as such because the negative and positive charges cancel, thus giving LiBr
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    well, what I learnt was this:

    The ion for Li is Li+1 and the ion for Br is Br-1
    So, you swap the powers (in this case they stay the same) and drop them (Li1Br1).
    You don't need 1's so get rid.

    Therefore, LiBr

    Hope that helps
 
 
 
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