How many moles of "Al" are needed to form 3.7 moles of "Al"_2"O"_3?

4"Al" + 3"O"_2 -> 2"Al"_2"O"_3

1 Answer

"7.4 mol Al"

Explanation:

The balanced chemical equation for it is

4Al + 3O_2 -> 2Al_2O_3

You have 3.7 moles of Al_2O_3. When you balanced the equation, you got 2 moles of "Al_2O_3 and 4 moles of Al, so

"4 mol Al gives 2 mol Al_2O_3

After you cancel out the units of measurement to check the order of the conversion, multiply 3.7 with 4 and then divide the answer by 2. You get 7.4 moles of Al.