In a single stage extraction process, 10 kg of pure solvent S (containing
no solute A) is mixed with 30 kg of feed F containing A at a mass fraction
xf = 0.2. The mixture splits into an extract phase E and a raffinate
phase R containing A at xB = 0.5 and xR = 0.05 respectively. The total mass
of the extract phase is (in Kg)
(A) 6.89
(B) 8.89
(C) 10
(D) 8.25