Percent yield or yield is mathematically defined as:
Yield = Actual amount / Theoretical amount
So to solve the yield, let us first calculate the theoretical amount of POCl3 produced. The balanced chemical reaction for this is:
6 PCl5 + P4O10 ---> 10 POCl3
Since P4O10 is stated to be supplied in large amount, then PCl5 becomes the limiting reactant.
So we calculate for POCl3 based on PCl5. To do this let us convert the amount into moles: (molar mass PCl5 = 208.24 g/mol)
n PCl5 = 42.66 grams / (208.24 g/mol)
n PCl5 = 0.205 mol
Now based on the stoichiometric ratio of the reaction:
n POCl3 = 0.205 mol (10
POCl3 / 6 PCl5)
n POCl3 = 0.3414 mol POCl3
Converting to mass (molar mass POCl3 = 153.33 g/mol)
m POCl3 = 0.3414 mol (153.33 g/mol)
m POCl3 = 52.35 g
Calculating for yield:
Yield = 47.22 g/ 52.35 g
Yield = 0.902
%Yield = 90.2 % (ANSWER)
