Question

One can prepare homemade lavender perfume by steam distillation,one of the main components in the lavender oil is linalyl acetare (MM 196 g/mol), which has a vapor pressure of 20 mm Hg at the boiling point of the mixture with water. If one collect 500 g of lavender from a garden and performs a codistillation with water, what would be the compositions of the distillate?

What does it mean by the "composition" of the distillate? Also, how do you figure out how much water was used to run this experiment?

Answer 1

Values:

P_t=20 mmHg (0.02631 atm)

T= 100°C (373.15 K)

V= ¿? Litters of waters

n_t= n_water + n_{linalyl-acetate}

R= 0.0821 atm.L.mol^-1.K^-1

Obtaining performance linalyl acetate = 36% w/w

If one collect 500 g of lavender from a garden and performs a codistillation with water, what would be the compositions of the distillate?

About linalyl acetate

Performance linalyl acetate in 500g of garden lavender = 500g (0.36) = 180 g

Linalyl acetate moles = 180g/190g.mol^-1=0.9473 mol of linalyl acetate

About water

According to the literature and empirical information, 8 liters of water are used to distill a kilogram, so 4 liters (4000g) of water would be used to distill lavender flowers 500g.

Water moles = 4000g/18g.mol^-1=222.22 mol

About the composition of the mixture

Total moles = 223.167 mol

Water mole fraction: X_water = (222.22mol/223.167mol)_x100%=99.57%

Linalyl acetate mole fraction: X_{linalyl-acetate}= (0.9473mol/223.16mol)_x100%=0.42%

What does it mean by the "composition" of the distillate?

Distillate composition , refers to the percentage of linalyl acetate and the percentage of water forming distillate volume received.

How do you figure out how much water was used to run this experiment?

According to the literature and empirical information, 8 liters of water are used to distill a kilogram, so 4 liters (4000g) of water would be used to distill lavender flowers 500g.