The ‘laughing gas’ is__________________?

Related Mcqs:

1. Velocity of a gas in sound is not proportional to (where, T = Absolute temperature of the gas. P = Absolute pressure of the gas. y = Ratio of specific heats (Cp/Cv) ρ = specific weight of the gas) ?

   A. √T
   B. 1/√P
   C. √y
   D. 1/√ρ

2. A gas which is collected over water becomes moistened due to water vapor, exerts its own partial pressure at the gas temperature, which is termed as its_______________?

   A. Aqueous tension
   B. Saturated humidity
   C. Vapor pressure
   D. Absolute humidity

3. Volumetric composition of flue gas analysed with the Orsat apparatus is : CO2 = 12%, O2 = 8%, CO = nil, N2 = 80%. This flue gas composition indicates that_________________?

   A. Pure oxygen has been used for combustion
   B. Nitrogen percentage in the fuel is very high
   C. Excess air has been used for combustion
   D. Hydrogen is not present in the fuel

4. Work required for compression of a gas contained in a cylinder is 7000 kJ. During compression, heat interaction of 3000 kJ causes the surroundings to be heated. Internal energy change of the gas during the compression is __________________ kJ ?

   A. +4000
   B. -4000
   C. 10000
   D. -10000

5. Oxide layer formed on the non-ferrous metal surface after its annealing is__________________?

   A. Removed by acid pickling
   B. Hammered into the surface
   C. Removed with coarse emery cloth
   D. Left as such to protect the surface

6. In case of condensers & evaporators operating under given terminal conditions, LMTD (logarithmic mean temperature difference) for counter flow as compared to that for parallel flow is__________________?

   A. More
   B. Less
   C. Equal
   D. Much more

7. Case hardening of a material is__________________?

   A. Followed by tempering or carburising
   B. Preceded by its tempering
   C. Done to get a soft ductile interior with a very hard surface
   D. Carried out to get extreme hardness in its core

8. According to thermodynamic Fahrenheit scale, the fundamental interval between ice point to steam point is__________________?

   A. 180°
   B. 212°
   C. 32°
   D. 273°

9. The refractory brick which has good thermal shock resistance at high temperature but cracks on cooling below 400°C is__________________?

   A. Magnesite
   B. Chrome
   C. Silica
   D. Fireclay

10. Pipelines carrying various utilities in chemical industries are identified by their colour codes. The color of pipeline carrying steam is__________________?

    A. Black
    B. Silver grey
    C. Green
    D. Yellow