Dry air is a mixture of__________________?

Related Mcqs:

1. Saturated solution of benzene in water is in equilibrium with a mixture of air and vapours of benzene and water at room temperature and pressure. Mole fraction of benzene in liquid is xB and the vapour pressures of benzene and water at these conditions are pv B and pv w respectively. The partial pressure of benzene in air-vapour mixture is_________________?

   A. PvB
   B. xB.PvB
   C. (Patm – Pvw)xB
   D. xB.Patm

2. A gas mixture contains 6 moles of H2 and 2 moles of N2. If the total pressure of the gaseous mixture is 4 kgf/cm2; then the partial pressure of N2 in the mixture will be _____________ kgf/cm2 ?

   A. 1
   B. 2
   C. 4
   D. 8

3. The boiling points for pure water and pure toluene are 100°C and 110.6°C respectively. Toluene and water are completely immiscible in each other. A well agitated equimolar mixture of toluene and water are prepared. The temperature at which the above mixture will exert a pressure of one standard atm. is___________________?

   A. Less than 100°C
   B. 100°C
   C. Between 100 and 110°C
   D. 110.6°C

4. Pure oxygen is mixed with air to produce an enriched air containing 50 volume % of oxygen. The ratio of moles of air to oxygen used is_________________?

   A. 1.72
   B. 0.58
   C. 0.5
   D. 0.2

5. A car tyre of volume 0.057 m3 is inflated to 300 kPa at 300 K. After the car is driven for 10 hours, the pressure in the tyre increases to 330 kPa. Assume air is an ideal gas and Cv for air is 21 J/mole.K. The change in the internal energy of air in the tyre in J/mole is__________________?

   A. 380
   B. 630
   C. 760
   D. 880

6. Pure aniline is evaporating through a stagnant air film of 1 mm thickness at 300 K and a total pressure of 100 KPa. The vapor pressure of aniline at 300 K is 0.1 KPa. The total molar concentration under these conditions is 40.1 mole/m3. The diffusivity of aniline in air is 0.74 × 10-5m2/s. The numerical value of mass transfer co-efficient is 7.4 × 10-3. Its units are_______________________?

   A. m/s
   B. cm/s
   C. mole/m2.s.Pa
   D. k.mole/m2.s.Pa

7. Heat capacity of air can be approximately expressed as, Cp = 26.693 + 7.365 x10-3 T, where, Cp is in J/mole.K and T is in K. The heat given off by 1 mole of air when cooled at atmospheric pressure from 500°C to – 100°C is ____________________?

   A. 10.73 kJ
   B. 16.15 kJ
   C. 18.11 kJ
   D. 18.33 kJ

8. Measurement of the amount of dry gas collected over water from volume of moist gas is based on the___________________?

   A. Charle’s law
   B. Dalton’s law of partial pressures
   C. Avogadro’s hypothesis
   D. Boyle’s law

9. The pressure of ‘V’ litres of a dry gas is increased from 1 to 2 kgf/cm2 at a constant temperature. The new volume will become___________________?

   A. V/2
   B. 2V
   C. V/4
   D. V2

10. The molar composition of a gas is 10% H2, 10% O2, 30% CO2 and balance H2O. If 50% H2O condenses, the final mole percent of H2 in the gas on a dry basis will be_______________?

    A. 10%
    B. 5%
    C. 18.18%
    D. 20%