Average molecular weight of air is about ____________________?

Related Mcqs:

1. The density of a gas ‘X’ is twice that of another gas ‘Y’. If the molecular weight of gas ‘Y’ is ‘M’; then the molecular weight of the gas ‘X’ will be________________?

   A. 2M
   B. M/2
   C. M
   D. M/4

2. Diffusion is that property by virtue of which a perfume bottle when opened up in a room, makes the whole room fragrant with its smell. If a perfume ‘X’ diffuses twice as fast as another perfume ‘Y’; what is the molecular weight of ‘Y’, if the vapor density of gas ‘X’ is 2? Molecular weight of gas ‘X’ is to be assumed to be 2 ?

   A. 2
   B. 4
   C. 8
   D. 16

3. 1 gm mole of an alcohol whose molecular weight is 74 contains 48 gms of carbon, 10 gms of hydrogen and 16 gms of oxygen. Its molecular formula is__________________?

   A. C4H9OH
   B. C3H21OH
   C. (C2H4)2H2.OH
   D. C2H33OH

4. 80 kg of Na2SO4 (molecular weight = 142) is present in 330 kg of an aqueous solution. The solution is cooled such that. 80 kg of Na2SO4 .10H2O crystals separate out. The weight fraction of Na2SO4 in the remaining solution is_________________?

   A. 0.00
   B. 0.18
   C. 0.24
   D. 1.00

5. The vapor pressure of liquids of similar chemical nature at any particular temperature _______________ with increase in the molecular weight?

   A. Increases
   B. Decreases
   C. Remains unchanged
   D. Either A. or B.; depends on the liquid

6. A fluid gas produced on burning furnace oil contains 0.15 gm mole of CO2, 0.05 gm mole of oxygen and 0.80 gm mole of N2. What is its molecular weight ?

   A. 28.6
   B. 30.0
   C. 30.6
   D. 32.6

7. The vapor pressure of liquids (having similar chemical nature) at any specified temperature ______________ with increasing molecular weight?

   A. Increases
   B. Decreases
   C. Remains unchanged
   D. Increases linearly

8. N2 content in a urea sample was found to be only 42%. What is the actual urea content of the sample? (Molecular weight of urea = 60) ?

   A. 80%
   B. 90%
   C. 95%
   D. 98%

9. 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

10. 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