--%>
Assignment Help - homework help

Explain solid in liquid solutions.

The French chemist Francois Marie Raoult (1886) carried out a series of experiments to study the vapour pressure of a number of binary solutions. On the basis of the results of the experiments, he proposed a generalization called Raoult's law which states that, 

The vapour pressure of a solution containing non-volatile solute is directly proportional to the mole fraction of the solvent.

In case of solution containing two components A (volatile solvent) and B (non-volatile solute) the vapour pressure of solution is given as

[Vapour pressure of solution] = [vapour pressure of solvent in solution (pA) ∝ [mole fraction of solvent (xA)]
                                                  
Or pA ∝ xA
                                                
Or, pA = kxA

Where k is proportionality constant.

For pure liquid, xA = 1 then k becomes equal to be vapour pressure of the pure solvent which is denoted by pA°.

Thus, pA = pA°xA                                            (i)

Or psolution × mole fraction of solvent.

For solutions obeying Raoult's law at all concentrations its vapour pressure would vary linearly from zero to the vapour pressure of pure solvent.

If mole fraction of solute is sB, then

xA + xB = 1 or xA = 1 - xB                             (ii)

From eqns. (i) and (ii),

pA = pA°(1 - xB) = pA° - pA°xB

Or, pA° - pA = pA°xB

2263_solids on liquids.png

   Related Questions in Chemistry

  • Q : Question on Raoults law Give me answer

    Give me answer of this question. For a dilute solution, Raoult's law states that: (a) The lowering of vapour pressure is equal to mole fraction of solute (b) The relative lowering of vapour pressure is equal to mole fraction of solute (c) The relative lowering of v

    		•
  • Q : Describe physical adsorption and its

    When the forces of attraction existing between adsorbate and adsorbent are van der Waal's forces, the adsorption is called physical adsorption. This type of adsorption is also known as physisorption or van der Waal's adsorption. Since the forces existing between adsorbent and adsorbate are very w

    		•
  • Q : Liquid Vapour Free Energies The free

    The free energy of a component of a liquid solution is equal to its free energy in the equilibrium vapour.Partial molal free energies let us deal with the free energy of the components of a solution. We use these free energies, or simpler concentration ter

    		•
  • Q : Finding Active mass of urea Can someone

    Can someone please help me in getting through this problem. 10 litre solution of urea comprises of 240 gm urea. The active mass of urea is: (i) 0.04 (ii) 0.02 (iii) 0.4 (iv) 0.2

    		•
  • Q : Determining of normality of sodium

    Can someone please help me in getting through this problem. The normality of a solution of sodium hydroxide 100 ml of which includes 4 grams of NaOH is: (a) 0.1 (b) 40 (c) 1.0 (d) 0.4

    		•
  • Q : Vapour pressure of the pure hydrocarbons

    Give me answer of this question. A solution has a 1 : 4 mole ratio of pentane to hexane. The vapour pressure of the pure hydrocarbons at 20°C are 440 mmHg for pentane and 120 mmHg for hexane. The mole fraction of pentane in the vapour phase would be: (a) 0.549 (b)

    		•
  • Q : Dipole moment Elaborate a dipole moment

    Elaborate a dipole moment?

    		•
  • Q : Donnan Membrane Equilibria The electric

    The electric charge acquired by macromolecules affects the equilibrium set up across a semipermeable membrane.Laboratory studies of macromolecule solutions as in osmotic pressure and dialysis studies confine the macromolecules to one compartment while allo

    		•
  • Q : Macromolecules what are condensation

    what are condensation polymerization give in with 2 examples

    		•
  • Q : Acid Solutions Choose the right answer

    Choose the right answer from following. Volume of water needed to mix with 10 ml 10N NHO3 to get 0.1 N HNO3: (a) 1000 ml (b) 990 ml (c) 1010 ml (d) 10 ml

    		•