State Raoult law and obtain expression forlowering of vapour pressure when nonvolatile solute is dissolved in solvent.

State Raoult law and obtain expression forlowering of vapour pressure

1.	State Raoult law and obtain expression forlowering of vapour pressure when nonvolatile solute is dissolved in solvent.
Answer» <P> Solution :Roult's LAW :This law states that " in the case of a solution of volatile liquids the partial vapour pressure of each component (A & B) of the solution is directly proportional to its mole fraction " ` P_(A) alpha X_A` ` (P_(A) ^(@)" is the vapour pressure of pure component") ` when ` X_A=1 , ` then k =` p_(A)^(@) ` ` P_(B) =p_B^(@) ,X_b ` When a nonvolatile solute is dissolved in a pure water the VAPOURPRESSURE of the solution will depend only the solvent molecules as the solute in non-volatile ` P_("solute ") PROP X_A ` ` P_("solution ") = k,X_A ` ` X_A =1, k =P_("solvent ")^(@)-P_("solution ") ` Relativelowering of vapour pressure ` =("P_(solvent ") ^(@) -P_("solution ") )/( P_("solvent ") ^(@) ) =X_B ` where ` X_B ` =Mole fraction of the solute.