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

Related Mcqs:

1. Sooty and sulphurous smog formed due to combustion of fossil fuels particularly in winter, continues throughout the day and night. When the moist atmospheric air’s water vapor condenses on the solid particles of smoke thereby forming smog (smoke + fog), it causes_________________?

   A. Poor visibility due to sky darkening
   B. Irritation in eyes
   C. Respiratory trouble
   D. All A., B. and C.

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

   A. Lower than
   B. Higher than
   C. Same as
   D. Not related to

3. One mole of methane undergoes complete combustion in a stoichiometric amount of air. The reaction proceeds as CH4 + 2O2 → CO2 + 2H2O. Both the reactants and products are in gas phase. ΔH°298 = – 730 kJ/mole of methane. Mole fraction of water vapour in the product gases is about_____________________?

   A. 0.19
   B. 0.33
   C. 0.40
   D. 0.67

4. Catalyst used in the ‘catalytic converter’ employed in automobile exhaust line for complete combustion/oxidation of carbon monoxide, nitrogen oxides and hydrocarbons is__________________?

   A. Alumina
   B. Platinum
   C. Vanadium pentoxide
   D. Iron oxide

5. Which of the following non-flow reversible compression processes require maximum work ?

   A. Adiabatic process
   B. Isothermal process
   C. Isobaric process
   D. All require same work

6. 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

7. 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

8. Major sources of noise in furnace operation arises from air inspirators, combustion, side wall vibrations and fluctuation in the process heat load. A 50% increase in fuel firing rate may increase the furnace noise level by about ____________ decibels?

   A. 3
   B. 30
   C. 7
   D. 70

9. The combustion equations of carbon and carbon monoxide are as follows: C + O2 = CO2, ΔH = – 394 kJ/kg .mole CO + ½ O2 = CO2, ΔH = – 284.5 kJ/kg. mole. The heat of formation of CO is _____________ kJ/kg. mole?

   A. -109.5
   B. +109.5
   C. +180
   D. +100

10. The accumulation in a steady state combustion process, burning 1 kg mole of carbon with 1 kg mole of oxygen thereby producing 1 kg mole of carbon dioxide, is _____________ kg mole?

    A. 1
    B. 0
    C. 16
    D. 44