--%>
Assignment Help - homework help

Molar mass of solute

The boiling point of benzene is 353.23 K. If 1.80 gm of a non-volatile solute was dissolved in 90 gm of benzene, the boiling point is increased to 354.11 K. Then the molar mass of the solute is:

(a) 5.8g mol-1  (b) 0.58g mol-1  (c) 58g mol-1  (d) 0.88 g mol-1         

Answer: (c) The elevation (ΔTb) in the boiling point
= 354.11 K - 353.23 K = 0.88 K
         
Substituting these values in expression
Msolute    = (Kb x 1000 x w)/ΔTb x W     
Where, w = weight of solute, W = weight of solvent
         
Msolute = (2.53 x 1.8 x 1000)/(0.88 x 90)  = 58 gm mol-1
Hence, molar mass of the solute = 58 gm mol-1

   Related Questions in Chemistry

  • Q : Why medications include the hcl Why do

    Why do various medications include the hcl? Describe briefly?

    		•
  • 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 : Number of moles of potassium chloride

    Choose the right answer from following. The number of moles of KCL in 1000ml of 3 molar solution is: (a)1 (b)2 (c)3 (d)1.5

    		•
  • Q : Mole fraction of water and ethanol Give

    Give me answer of this question. A solution contains 1 mole of water and 4 mole of ethanol. The mole fraction of water and ethanol will be: (a) 0.2 water + 0.8 ethanol (b) 0.4 water + 0.6 ethanol (c) 0.6 water + 0.8 ethanol (d) 0.8 water + 0.2 ethanol

    		•
  • Q : Vapour pressure of a liquid Help me to

    Help me to go through this problem. The vapour pressure of a liquid depends on: (a) Temperature but not on volume (b) Volume but not on temperature (c) Temperature and volume (d) Neither on temperature nor on volume

    		•
  • Q : Raoults law Give me answer of this

    Give me answer of this question. Provide solution of this question. Which one of the following is the expression of Raoult's law: (a) P-P1/P = n/n+N (b) P1-P/P = N/ N+n (c)P-P2/P1= N/ N-n (d) P1-P/P2= N-n/N

    		•
  • Q : Vapour pressure of volatile substance

    Provide solution of this question. According to Raoult's law the relative lowering of vapour pressure of a solution of volatile substance is equal to: (a) Mole fraction of the solvent (b) Mole fraction of the solute (c) Weight percentage of a solute (d) Weight perc

    		•
  • Q : Concentration of an aqueous solution

    Give me answer of this question. The concentration of an aqueous solution of 0.01M CH3OH solution is very nearly equal to which of the following : (a) 0.01%CH3OH (b) 0.1%CH3OH (c) xCH3OH= 0.01 (d) 0.99MH2O (

    		•
  • Q : Problem on decomposition reaction

    Nitrogen tetroxide (melting point: -11.2°C, normal boiling point 21.15°C) decomposes into nitrogen dioxide according to the following reaction: N2O4(g) ↔ 2 NO2(g)<

    		•
  • Q : Explain alcohols and phenols in organic

    Alcohols and phenols are the compounds

    		•