Magnesium oxide can be made by heating magnesium metal in the presence of oxygen. The balanced equation for the reaction is: 2Mg(s)+O2(g)→2MgO(s) When 10.1 g of Mg are allowed to react with 10.5 g of O2, 10.3 g of MgO are collected. Dteremine the limiting reactants for the reaction

Respuesta :

Answer: The limiting reactants for the reaction is, Mg

Explanation : Given,

Mass of [tex]Mg[/tex] = 10.1 g

Mass of [tex]O_2[/tex] = 10.5 g

Molar mass of [tex]Mg[/tex] = 24 g/mol

Molar mass of [tex]O-2[/tex] = 32 g/mol

First we have to calculate the moles of [tex]Mg[/tex] and [tex]O_2[/tex].

[tex]\text{Moles of }Mg=\frac{\text{Given mass }Mg}{\text{Molar mass }Mg}[/tex]

[tex]\text{Moles of }Mg=\frac{10.1g}{24g/mol}=0.421mol[/tex]

and,

[tex]\text{Moles of }O_2=\frac{\text{Given mass }O_2}{\text{Molar mass }O_2}[/tex]

[tex]\text{Moles of }O_2=\frac{10.5g}{32g/mol}=0.328mol[/tex]

Now we have to calculate the limiting and excess reagent.

The balanced chemical equation is:

[tex]2Mg(s)+O_2(g)\rightarrow 2MgO(s)[/tex]

From the balanced reaction we conclude that

As, 2 mole of [tex]Mg[/tex] react with 1 mole of [tex]O_2[/tex]

So, 0.421 moles of [tex]Mg[/tex] react with [tex]\frac{0.421}{2}=0.2105[/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]Mg[/tex] is a limiting reagent and it limits the formation of product.

Hence, the limiting reactants for the reaction is, Mg