We have the following chemical reaction:
P₄ + 10 Cl₂ → 4 PCl₅
<u>Identifying the limiting reactant.</u>
mass of P₄ = 28 g
mass of Cl₂ = 53 g
number of moles = mass / molecular weight
number of moles of P₄ = 28 / 124 = 0.226 moles
number of moles of Cl₂ = 53 / 71 = 0.746 moles
From the reaction we see that 1 mole of P₄ will react with 10 moles of Cl₂ so 0.226 moles of P₄ will react with 2.226 moles of Cl₂, but we have only 0.746 moles of Cl₂. So the limiting reactant will be Cl₂.
<u>Part B</u>
From the previous calculations we know that 28 g of P₄ are equal to 0.226 moles moles of P₄.
Now, knowing the chemical reaction, we devise the following reasoning:
if 1 mole of P₄ produces 4 moles of PCl₅
then 0.226 moles of P₄ produces X moles of PCl₅
X = (0.226 × 4) / 1 = 0.904 moles of PCl₅
<u>Part C</u>
From the previous calculations we know that 53 g of Cl₂ are equal to 0.746 moles moles of Cl₂.
Now, knowing the chemical reaction, we devise the following reasoning:
if 10 moles of Cl₂ produces 4 moles of PCl₅
then 0.746 moles of Cl₂ produces X moles of PCl₅
X = (0.746 × 4) / 10 = 0.298 moles of PCl₅