Answer : The limiting reactant is, carbon (C)
Explanation : Given,
Moles of [tex]SiO_2[/tex] = 2 moles
Moles of C = 5 moles
Now we have to calculate the limiting and excess reagent.
The given balanced chemical reaction is:
[tex]SiO_2+3C\rightarrow SiC+2CO[/tex]
From the balanced reaction we conclude that
As, 3 mole of [tex]C[/tex] react with 1 mole of [tex]SiO_2[/tex]
So, 5 moles of [tex]C[/tex] react with [tex]\frac{5}{3}=1.67[/tex] moles of [tex]SiO_2[/tex]
From this we conclude that, [tex]SiO_2[/tex] is an excess reagent because the given moles are greater than the required moles and [tex]C[/tex] is a limiting reagent and it limits the formation of product.
Thus, the limiting reactant is, carbon (C)