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    I need help with this question:2.07g of element Z with bromine to form 3.67g of a compound with an emperical formula of ZBr2. Find the relative atomic mass of element Z.Please teach me the steps to get the answer.(I do not have the answer)
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    Mass is conserved in chemical reactions. So 2.07 g of that 3.67 g is Z, meaning 3.67 - 2.07 g is Br.

    So work out the mass of Br, then convert it to moles by dividing it by the molar mass of bromine (79.903)

    And in the formula given, ZBr2, there is 2 moles of Br for every 1 mole of Z, so the moles of Z in that compound must be 1/2 the moles of Br, so divide the moles of Br by 2.

    Now you know the mass of Z and the moles of Z, so you can work out the molar mass of Z. n = m / M, rearrange that to solve for M.
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    This may help:

    https://tinyurl.com/ybfrad8r
 
 
 
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