What is the theoretical yield of bromobenzene in this reaction when 32.0 g of benzene reacts with 69.3 g of bromine?

Respuesta :

First calculate the number of moles of bromine and benzene.

Number of moles = [tex]\frac{given mass in g}{molar mass}[/tex]

Mass of benzene = [tex]32.0 g[/tex] (given)

Molar mass of benzene=  [tex]78.11 g/mol[/tex]

Substitute the above values in formula, we get

Number of moles of benzene= [tex]\frac{32.0 g}{78.11 g/mol}[/tex]

= [tex]0.409 mol[/tex]

Mass of bromine = 69.3 g

Molar mass of bromine = [tex]2\times 79.9 g/mol[/tex] = [tex]159.8 g/mol[/tex]

Substitute the above values in formula, we get

Number of moles of benzene= [tex]\frac{69.3 g}{159.8 g/mol}[/tex]

= [tex]0.43 g/mol[/tex]

Now, ratio of benzene and bromine comes out be 1:1 respectively and limiting reagent is benzene because present less as compared to bromine.

Thus, number of moles of bromobenzene = [tex]0.409 mol[/tex]

Theoretical yield = [tex]number of moles \times molar mass[/tex]

= [tex]0.409 mol \times 157.02 g/mol[/tex]   (molar mass of bromonenzene = 157.02 g/mol)

= [tex]64.22118 g[/tex]

Hence, theoretical yield of bromobenzene is [tex]64.22118 g[/tex]