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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)

    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.

    This may help:

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