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Chemical Engineering :: Stoichiometry

  1. A gas occupies a volume of 283 c.c at 10°C. If it is heated to 20°C at constant pressure, the new volume of the gas will be __________ c.c.

  2. A.

     283

    B.

     566

    C.

     293

    D.

     141.5


  3. The latent heat of vaporisation

  4. A.

     Decreases with increased temperature

    B.

     Decreases as pressure increases

    C.

     Becomes zero at the critical point

    D.

     All of the above


  5. A solution is made by dissolving 1 kilo mole of solute in 2000 kg of solvent. The molality of the solution is

  6. A.

     2

    B.

     1

    C.

     0.5

    D.

     0.5


  7. If the partial pressure of the solvent in the vapor phase is equal to the vapor pressure of the solvent at that temperature, then the system is said to be at its

  8. A.

     Bubble point

    B.

     Saturation temperature

    C.

     Dew point

    D.

     Both B and C


  9. If the pressure of a gas is reduced to half & its absolute temperature is doubled, then the volume of the gas will

  10. A.

     Be reduced to l/4th

    B.

     Increase four times

    C.

     Increase two times

    D.

     None of these


  11. Disappearance of snow in subzero weather exemplifies the process of

  12. A.

     Evaporation

    B.

     Sublimation

    C.

     Vaporisation

    D.

     Melting


  13. At 100°C, water and methylcyclohexane both have vapour pressures of 1 atm. Also at 100°C, the latent heats of vaporisation of these compounds are 40.63 kJ/mole for water and 31.55 kJ/mole for methylcyclohexane. The vapour pressure of water at 150°C is 4.69 atm. At 150°C, the vapour pressure of methylcyclohexane would be expected to be

  14. A.

     Significantly less than 4.69 atm

    B.

     Nearly equal to 4.69 atm

    C.

     Significantly more than 4.69 atm

    D.

     Indeterminate due to lack of data


  15. If a solution of eutectic composition is cooled, __________ reaching the eutectic temperature.

  16. A.

     The solvent begins to freeze out even before

    B.

     It will undergo no change until

    C.

     It will not solidify even on

    D.

     None of these


  17. If 1.5 moles of oxygen combines with aluminium to form Al2O₃, then the weight of aluminium (atomic weight = 27 ) used in this reaction is __________ gm.

  18. A.

     27

    B.

     54

    C.

     5.4

    D.

     2.7


  19. Pick out the wrong statement.

  20. A.

     Atomic heat capacities of the crystalline solid elements are nearly constant and equal to 6.2 kcal/kg-atom according to the law of Petit and Dulong

    B.

     Atomic heat capacities of all solid elements decrease greatly with decrease in temperature, approaching a value of zero at absolute zero temperature, when in the crystalline state

    C.

     Generally, the heat capacities of compounds are lower in the liquid than in the solid state

    D.

     The heat capacity of a heterogeneous mixture is an additive property, but when solutions are formed, this additive property may no longer exist