Question

40 mole% of A in liquid phase is equilibrium with 70 mole% of B in vapour phase. Determine ratio of P*A and P*B.​

Answer 1

Answer:

3.5

Explanation:

From Raoult's law

.. PA = (P*A) x (χA)

.. PB = (P*B) x (χB).. .. .. . χB is mole fraction B in LIQUID phase

and from Daltons law

.. PA = yA x Ptotal

.. PB = yB x Ptotal.. .. ... ...yB is mole fraction B in VAPOR phase

subbing

.. yA x Pt = (P*A) x (χA)

.. yB x Pt = (P*B) x (χB)

dividing

.. (yA / yB) x (Pt / Pt) = (P*A / P*B) x (χA / χB)

simplifying and rearranging

.. (P*A / P*B) = (yA / yB) x ((χB / χA)

and finally

.. (P*A / P*B) = (60 / 40) x (70 / 30) = 3.5From Raoult's law

.. PA = (P*A) x (χA)

.. PB = (P*B) x (χB).. .. .. . χB is mole fraction B in LIQUID phase

and from Daltons law

.. PA = yA x Ptotal

.. PB = yB x Ptotal.. .. ... ...yB is mole fraction B in VAPOR phase

subbing

.. yA x Pt = (P*A) x (χA)

.. yB x Pt = (P*B) x (χB)

dividing

.. (yA / yB) x (Pt / Pt) = (P*A / P*B) x (χA / χB)

simplifying and rearranging

.. (P*A / P*B) = (yA / yB) x ((χB / χA)

and finally

.. (P*A / P*B) = (60 / 40) x (70 / 30) = 3.5From Raoult's law

.. PA = (P*A) x (χA)

.. PB = (P*B) x (χB).. .. .. . χB is mole fraction B in LIQUID phase

and from Daltons law

.. PA = yA x Ptotal

.. PB = yB x Ptotal.. .. ... ...yB is mole fraction B in VAPOR phase

subbing

.. yA x Pt = (P*A) x (χA)

.. yB x Pt = (P*B) x (χB)

dividing

.. (yA / yB) x (Pt / Pt) = (P*A / P*B) x (χA / χB)

simplifying and rearranging

.. (P*A / P*B) = (yA / yB) x ((χB / χA)

and finally

.. (P*A / P*B) = (60 / 40) x (70 / 30) = 3.5