Periclase is___________________?

Related Mcqs:

1. Periclase refractory contains mainly________________?

   A. CaO
   B. MgO
   C. Al2O3
   D. SiO2

2. Quartz is___________________?

   A. Stable form of silica upto 870°C
   B. Converted to Tridymite on firing between 870 to 1470°C
   C. Transformed to Cristobalite on heating above 1470°C
   D. All A., B. and C.

3. The highest melting pure oxide (m.p. > 3000°C)is___________________?

   A. Thoria
   B. Alumina
   C. Beryllia
   D. Zirconia

4. ______________ bricks are used in the burning zone of a cement rotary kiln ?

   A. High alumina
   B. Fireclay
   C. Thoria
   D. Silicon carbide

5. Machine moulding of dry mixture of refractories requires a pressure of the order of _____________ kg/cm2?

   A. 10
   B. 100
   C. 500
   D. 1000

6. Which one expands on heating ?

   A. Silica bricks
   B. Fireclay bricks
   C. Both A. & B.
   D. Neither A. nor B.

7. Mixing of ground refractory material and water is done in a ______________ mill?

   A. Pug
   B. Ball
   C. Tube
   D. Rod

8. Chemically, mullite refractories is____________________?

   A. 3Al2O3.2SiO2
   B. Al2O3
   C. ZrSO4
   D. ThO2

9. Maximum safe working temperature for fireclay bricks is about __________ °C?

   A. 1150
   B. 1300
   C. 1450
   D. 1550

10. Pure bauxite is the best raw material for the manufacture of high alumina refractories, in which maximum alumina content can be as high as _____________ percent?

    A. 55
    B. 70
    C. 80
    D. 90