With increase in the alumina content, the refractoriness of high alumina refractories_________________?

Related Mcqs:

1. Maximum alumina content in high alumina refractory can be as high as ____________ percent?

   A. 30 B. 50 C. 70 D. 90...

2. Beryllia (which is used in making crucibles for melting uranium & thorium) is superior to alumina in all respects for high temperature (> 1900°C ) use, except______________?

   A. Cost B. Electrical conductivity C. Thermal conductivity D. Fusion point...

3. Refractoriness/fusion points of ‘Superduty’ refractories is _____________ °C?

   A. 1520-1630 B. 1630-1670 C. > 1730 D. > 2000...

4. Presence of MgO in alumino-silicate refractories ______________ its refractoriness ?

   A. Increases B. Lowers C. Does not affect D. Either A. or B.; depends on its quantity...

5. 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%...

6. Thermal diffusivity of a refractory brick is high, when its ______________ is high?

   A. Density B. Specific heat C. Thermal conductivity D. None of these...

7. Water content in ground refractory material to be shaped into bricks by hand moulding is about _____________ percent?

   A. 5 B. 20 C. 40 D. 55...

8. The increase in the temperature of the aqueous solution will result in decrease of its________________?

   A. Weight % of the solute B. Mole fraction of the solute C. Molarity D. Molality...

9. With increase in temperature, the surface tension of water _____________________?

   A. Increases B. Decreases C. Remain constant D. Increases linearly...

10. In general, the specific heats of aqueous solutions _____________ with increase in the concentration of the solute?

    A. Increase B. Decrease C. Remain unchanged D. None of these...