What is the limiting reactant when 4.5 moles of aluminum react with 6.7 moles of oxygen gas? Unbalanced equation: Al + O2 → Al2O3 Show, or explain, all of your work along with the final answer.

4Al + 3O₂ -----> 2Al₂O₃
4 mol 3 mol

4 moles of aluminium react with 3 moles of oxygen
4,5 moles of aluminium need........???

4 mol Al -------- 3 mol O₂
4,5 mol Al ----- X
X = 3,375 mol

--- 4,5 moles of aluminium need 3,375 moles of oxygen.
We used 6,7 moles of oxygen, it's too much. So, oxygen is excess reactant and aluminium is limiting reactant.

:•)

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Alleei Alleei · Answer 2 · 2019-07-03T07:08:40+02:00

Answer : The limiting reagent is, Aluminum (Al)

Explanation : Given,

Given moles of Al = 4.5 moles

Given moles of [tex]O_2[/tex] = 6.7 moles

First we have to calculate the limiting and excess reagent.

The balanced chemical reaction is,

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

From the given balanced reaction, we conclude that

As, 4 moles of [tex]Al[/tex] react with 2 moles of [tex]O_2[/tex]

So, 4.5 moles of [tex]Al[/tex] react with [tex]\frac{2}{4}\times 4.5=3.375[/tex] moles of [tex]O_2[/tex]

From this we conclude that, [tex]O_2[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]Al[/tex] is a limiting reagent because it limits the formation of product.

Hence the limiting reagent is, Aluminum (Al)