--%>
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 : Define Virial Equation The constant of

    The constant of vander Waal's equation can be related to the coefficients of the virial equation.  Vander Waal's equation provides a good overall description of the real gas PVT behaviour. Now let us

    		•
  • Q : Molar concentration of hydrogen 20 g of

    20 g of hydrogen is present in 5 litre of vessel. Determine he molar concentration of hydrogen: (a) 4  (b) 1 (c) 3 (d) 2 Choose the right answer from above.

    		•
  • Q : Mole fraction and Molality Select the

    Select the right answer of the following question.What does not change on changing temperature : (a) Mole fraction (b) Normality (c) Molality (d) None of these

    		•
  • Q : Problem on molarity-normality-molality

    Can someone please help me in getting through this problem. The solution ofAl2(SO4)3 d = 1.253gm/m comprise 22% salt by weight. The molarity, normality and molality of the solution is: (1) 0.805 M, 4.83 N, 0.825 M (2)

    		•
  • Q : Explain Rotational Vibrational Spectra

    The infrared spectrum of gas samples shows the effect of rotational-energy changes along with the vibrational energy change.As we know from the interpretations given to thermodynamic properties of gases, gas molecules are simultaneously rotating and vibrating. It follows that an absor

    		•
  • Q : What are isotonic and hypotonic

    The two solutions which are having equivalent osmotic pressure are called isotonic solutions. The isotonic solutions at the same temperature also have same molar concentration. If we have solutions having different osmotic pressures then the solution having different

    		•
  • Q : Simulate the column in HYSYS The

    The objective of this work is to separate a binary mixture and to cool down the bottom product for storage. (Check table below to see which mixture you are asked to study). 100 kmol of feed containing 10 mol percent of the lighter component enters a continuous distillation column at the m

    		•
  • Q : Problem on mole fraction of glucose

    Provide solution of this question. While 1.80gm glucose dissolve in 90 of H2O , the mole fraction of glucose is: (a) 0.00399 (b) 0.00199 (c) 0.0199 (d) 0.998

    		•
  • Q : Decision about dipole moment is present

    How can you decide if there is a dipole moment or not?

    		•
  • Q : Production of alcoholic drinks give all

    give all physical aspects in the production of alcohol

    		•