Question

Calculate the percent yield of adipic acid from the oxidation of cyclohexanone with potassium permanganate:

Actual yield of adipic acid: 0.024 g

Moles of cyclohexanone used: 0.0025 mol

Moles of potassium permanganate used: 0.0050 mol

Density of cyclohexanone: 0.9478 g/ml

MW of cyclohexanone: 98.15 g/mol

MW of potassium permanganate: 158.03 g/mol

MW of adipic acid: 146.14 g/mol

Answer 1

Sol:-

Balanced Chemical equation is :

C₆H₁₀O......+.......2 KMnO₄ ...+.....H₂O---------> C₆H₁₀O₄.......+.......2 KOH

Cyclohexanone..................................................Adipic acid......................

From balanced oxidation equation it is cleared that

1 mole of Cyclohexanone reacts with = 2 moles of potassium permanganate

so

0.0025 moles of Cyclohexanone reacts with = 2 x 0.0025 moles of potassium permanganate

0.0025 moles of Cyclohexanone reacts with = 0.0050 moles of potassium permanganate

since given amount of potassium permanganate is also same i.e 0.0050 moles therefore both reactants get consumed in chemical reaction i.e amount of reactants left = 0

again from the balanced chemical equation

1 mole of Cyclohexanone gives= 1mole of Adipic acid

so

0.0025 moles of Cyclohexanone gives= 0.0025 moles of Adipic acid

we know

Number of moles = mass of substance in g / gram molar mass of substance

so

mass of Adipic acid in g = number of moles of adipic acid x Gram molar mass of adipic acid

mass of Adipic acid in g =0.0025 mol x 146.14 g/mol = 0.36535 g

so

Theoretical yield of adipic acid = 0.36535 g

given Actual yield of adipic acid = 0.024 g

Now

Percent yield = Actual yield of adipic acid x 100 / Theoretical yield %

Percent yield = 0.024 g x 100 / 0.36535 g %

Percent yield = 6.57 %