Regeneration of molecular sieve requires it to be heated to a temperature of about __________________ °C?

Related Mcqs:

1. Austempering of steel requires it to be heated to 875°C followed by sudden cooling to 250- 525°C, thereby changing austenite to___________________?

   A. Sorbite
   B. Bainite
   C. Martensite
   D. Troostite

2. 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

3. The boiling & freezing points on a newly defined temperature scale in degree ‘D’ are 400°D & 100°D respectively. The temperature reading corresponding to 60°C on this new temperature scale will be equal to _____________ °D ?

   A. 140
   B. 180
   C. 240
   D. 280

4. Heating the Hypo-eutectoid steels to 30°C above the upper critical temperature line, soaking at that temperature and then cooling slowly to the room temperature to form a pearlite & ferrite structure is called_______________________?

   A. Tempering
   B. Hardening
   C. Annealing
   D. Normalising

5. The ratio of thermal & electrical conductivity is same for all the metals at the same temperature; and at around room temperature, this ratio is proportional to(where, T = absolute temperature, °K) ?

   A. T
   B. 1/T
   C. T2
   D. 1/T2

6. Dry saturated steam can be converted into super heated steam by____________________?

   A. Increasing its cross-sectional area of flow
   B. Passing it through a pressure reducing valve
   C. Forcing it downwards through a vertical tube
   D. None of these

7. In case of water (Prandtl number ≈ 6) flowing over a flat plate heated over the entire length, the thermal boundary layer thickness as compared to hydrodynamic boundary layer thickness is ?

   A. Less
   B. More
   C. Equal
   D. Unpredictable

8. Hardening of steel is not possible, unless it is heated _________________ critical point ?

   A. Above the highest
   B. Above the lowest
   C. Between the first & second
   D. Between the second & third

9. Absolute zero, pressure will occur, when the molecular momentum of the system becomes zero. A liquid will cease to exist as liquid at________________?

   A. High vacuum
   B. Zero pressure
   C. 0°K
   D. Earth’s centre

10. __________________ of air does not increase with increase in temperature?

    A. Density
    B. Thermal diffusivity
    C. Viscosity
    D. Thermal conductivity