Home
Class 12
CHEMISTRY
The cryoscopic constant and freezing poi...

The cryoscopic constant and freezing point of benzene is `"5.12 K kg mol"^(-1)` and 278.6 K respectively. At what temperature will one molal solution of benzene containing a nonelectrolyte `(i=1)` freeze? 

Text Solution

Verified by Experts

Depression in breezing point `(DeltaT_(f))` for dilute solution is directly proportional to molality
`DeltaT_(f)alpham`
`DeltaT_(f)=K_(f)m`
`"Given : "K_(f)="5.12 K kg mol"^(-1)`
`T_(f)^(@)=278.6K`
`m="1 molal          "DeltaT_(f)=5.12 xx1`
`"                "DeltaT_(f)=5.12K`
`W.K.T"       "Delta_(f)=T_(f)^(@)-T_(f)`
`5.12 =278.6-T_(f)`
`T_(f)=278.6-5.12`
`T_(f)=273.48K`
Promotional Banner

Topper's Solved these Questions

  • II PUC CHEMISTRY (P.U. BOARD LATEST MODEL QUESTION PAPER - 2)

    SUNSTAR PUBLICATION|Exercise PART - B|9 Videos

  • II PUC CHEMISTRY (P.U. BOARD LATEST MODEL QUESTION PAPER - 2)

    SUNSTAR PUBLICATION|Exercise PART - C|10 Videos

  • II PUC CHEMISTRY (P.U. BOARD LATEST MODEL QUESTION PAPER - 1)

    SUNSTAR PUBLICATION|Exercise PART - D|25 Videos

  • II PUC CHEMISTRY (P.U. BOARD LATEST MODEL QUESTION PAPER - 3)

    SUNSTAR PUBLICATION|Exercise PART - D|30 Videos

Similar Questions

Explore conceptually related problems

A molal solution is one that contains 1 mol of a solute in

The ebullioscopic constant for benzene is 2.52 K Kg mol^(-1) . A solution of an organic substance in benzene boils at 0.125^(@)C higher than benzene. Calculate the molality of solution?

A solution containing 0.1 mol of naphthalene and 0.9 mol of benzene is cooled out until some benzene freezes out. The solution is then decanted off from the solid and warmed upto 353 K where its vapour pressure was found to be 670 mm . The freezing point and boiling point of benzene are 278.5 K and 353 K respectively, and its enthalpy of fusion is 10.67 KJ "mol"^(-1) . Calculate the temperature to which the solution was cooled originally and the amount of benzene that must have frozen out. Assume ideal behaviour.

The freezing point of a 0.05 molal solution of a non-eletrolyte in water is ( K_(f)=1.86Km^(-1) )

The molal freezing point depression constant of benzene (C_(6)H_(6)) is 4.90 K kg mol^(-1) . Selenium exists as a polymer of the type Se_(x) . When 3.26 g of selenium is dissolved in 226 g of benzene, the observed freezing point is 0.112^(@)C lower than pure benzene. Deduce the molecular formula of selenium. (Atomic mass of Se=78.8 g mol^(-1) )

The freezing point of 0.02 mole fraction acetic acid in benzene is 277.4 K . Acetic acid exists partly as dimer. Calculate the equilibrium constant for dimerization. The freezing point of benzene is 278.4 K and the heat the fusion of benzene is 10.042 kJ mol^(-1) . Assume molarity and molality same.

(a) 10 g of non-electrolyte solute dissolved in 50 g of benzene lowered the freexing point of benzene by 0.4 K. Find the molar mass of the solute.[Given : Freezing point depression constant of benzene = 5.12 K. kg mor^(-1)] (b) How solubility of a gas in liquid varies with (i) Temperature and (ii) pressure?

A very small amount of a non-volatile solute (that does not dissociate) is dissolved in 56.8 cm^(3) of benzene (density 0.889 g cm^(3)) . At room temperature, vapour pressure of this solution is 98.88 mm Hg while that of benzene is 100 mm Hg . Find the molality of this solution. If the freezing temperature of this solution is 0.73 degree lower than that of benzene, what is the value of molal the freezing point depression constant of benzene?

SUNSTAR PUBLICATION-II PUC CHEMISTRY (P.U. BOARD LATEST MODEL QUESTION PAPER - 2)-PART - D
  1. The cryoscopic constant and freezing point of benzene is "5.12 K kg mo...

    Text Solution

    |

  2. Caleulate the packing efficiency in a unit cell of Cubic Close Packing...

    Text Solution

    |

  3. Explain with an example how impurity defect develops in NaCl crystal.

    Text Solution

    |

  4. Calculate the mole fraction of Co, in one litre of soda water sealed u...

    Text Solution

    |

  5. What are these? i) solid solutions ii) colligative properties iii) i...

    Text Solution

    |

  6. a) i) Name the product liberated at anode when dil. H(2)SO(4) is elect...

    Text Solution

    |

  7. ii) What Faraday of current is required to electrolyse one mole of wat...

    Text Solution

    |

  8. b) i) Between mercury cell and nickel-cadmium cell, which is a seconda...

    Text Solution

    |

  9. Mention one advantage of H(2) - O(2) fuel cell.

    Text Solution

    |

  10. c) Write Nernst equation for the cell represented as: Mg(s)|Mg((aq))^(...

    Text Solution

    |

  11. Show that for a first order reaction, t(99.9%)=10t(1//2).

    Text Solution

    |

  12. b) In the graph drawn what does A and the shaded region B represent?

    Text Solution

    |

  13. Name the phenomenon/process involved i) mixing of hydrated ferric ox...

    Text Solution

    |

  14. Mention any two characteristic of enzyme catalysis.

    Text Solution

    |

  15. a) Write the equation for SN^(2) mechanism between CH(3)Cl and -OH. Wh...

    Text Solution

    |

  16. b i) Aryl halide with sodium in dry ether undergoes Fitting reaction. ...

    Text Solution

    |

  17. a) What is the organic compound formed in the following :

    Text Solution

    |

  18. b) Give reason: - i) o-nitrophenol and p-nitrophenol can be separate...

    Text Solution

    |

  19. a) Write the structure of P and Q? Name the reaction that gives the pr...

    Text Solution

    |

  20. Explain decarboxylation reaction with an example.

    Text Solution

    |

  21. a) Name the products X and Y?

    Text Solution

    |