Answer:
The balanced chemical equation is
[tex]2AlCl_3 +3 Br_2 \Rightarrow 2 AlBr_3 + 3Cl_2[/tex]
The conversions are
mass [tex]AlCl_3[/tex] to moles [tex]AlCl_3[/tex] to moles [tex]Br_2[/tex] to mass [tex]Br_2[/tex]
To convert mass [tex]AlCl_3[/tex] to moles [tex]AlCl_3[/tex] we divide the mass by molar mass [tex]AlCl_3[/tex] which is
[tex]26.9+(3\times35.5)=133.34 g/mol[/tex]
To convert moles [tex]AlCl_3[/tex] to moles [tex]Br_2[/tex] we make use of mole ratio 2 : 3
To convert moles [tex]Br_2[/tex] to mass [tex]Br_2[/tex] we multiply by molar mass [tex]Br_2[/tex] which is
[tex]80 \times 2=160 (g )/mol[/tex]
[tex]$37.4 g A l C l_{3} \times \frac{1 m o l A l C l_{3}}{133.34 g A l C l_{3}} \times \frac{3 m o l B r_{2}}{2 m o l A l C l_{3}} \times \frac{160 g B r_{2}}{1 m o l B r_{2}}$[/tex]
=67.2g [tex]Br_2[/tex] is required (Answer).
