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How many grams of Al2O3 can be formed when 3.33 moles of Al and 4.87 moles of O2 react according to the following balanced equation: 4 Al + 3 O2 --> 2 Al2O3 (Hint: find the limiter first!) Express the answer to 3 sig figs. Do NOT include units.

Answer value

Respuesta :

Answer:  170 grams of [tex]Al_2O_3[/tex]

Explanation:

The balanced chemical reaction is:

[tex]4Al+3O_2(g)\rightarrow 2Al_2O_3[/tex]  

According to stoichiometry :

4 moles of [tex]Al[/tex] require = 3 moles of [tex]O_2[/tex]

Thus 3.33 moles of [tex]Al[/tex] will require=[tex]\frac{3}{4}\times 3.33=2.49moles[/tex]  of [tex]O_2[/tex]

Thus [tex]Al[/tex] is the limiting reagent as it limits the formation of product and [tex]O_2[/tex] is the excess reagent.

As 4 moles of [tex]Al[/tex] give = 2 moles of [tex]Al_2O_3[/tex]

Thus 3.33 moles of [tex]Al[/tex] give =[tex]\frac{2}{4}\times 3.33=1.67moles[/tex]  of [tex]Al_2O_3[/tex]

Mass of [tex]Al_2O_3=moles\times {\text {Molar mass}}=1.67moles\times 101.96g/mol=170g[/tex]

Thus 170 g of [tex]Al_2O_3[/tex] will be produced.