The maximum adiabatic flame temperature of fuels in air is ____________ the maximum flame temperature in pure oxygen?

Related Mcqs:

1. 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

2. _____________ fuels require the maximum percentage of ‘excess air’ for complete combustion ?

   A. Solid
   B. Liquid
   C. Gaseous
   D. Nuclear

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. For water evaporating into unsaturated air under adiabatic conditions and at constant pressure, the ____________ remains constant throughout the period of vaporisation ?

   A. Dry bulb temperature
   B. Wet bulb temperature
   C. Humidity
   D. Relative saturation

5. 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

6. 40 gms each of the methane and oxygen are mixed in an empty container maintained at 40°C. The fraction of the total pressure exerted by oxygen is_________________?

   A. 1/2
   B. 1/3
   C. 1/4
   D. 2/3

7. What fraction of the total pressure is exerted by oxygen, if equal weights of oxygen and methane are mixed in an empty vessel at 25°C ?

   A. 2/3
   B. 1/3
   C. 1/2
   D. 1/3 × (298/273)

8. 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

9. 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

10. With increase in the temperature of pure (distilled) water, its____________________?

    A. pOH decreases and pH increases
    B. pOH and pH both decreases
    C. pH and pOH both increases
    D. pH decreases and pOH increases