_____________ is not a single oxide-refractory?

Related Mcqs:

1. Thoria is an expensive refractory material and is radioactive in nature. Thorium oxide is used in the manufacture of______________?

   A. Segar cones
   B. Muffles for muffle furnaces
   C. Insulating bricks
   D. Crucibles used for melting of high purity metals

2. Highest melting (m.p = 3070°C) oxide refractory is__________________?

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

3. Sillimanite (Al2O3.SiO2) refractory, which is a neutral refractory, is not used in________________?

   A. Pottery furnace
   B. Glass melting furnace
   C. Crucibles
   D. Gas retorts

4. Maximum water percentage in refractory mix meant for hand moulding may be as high as _____________ percent?

   A. 2-3
   B. 5-7
   C. 7-12
   D. 14-20

5. Maximum alumina content in high alumina refractory can be as high as _____________ percent?

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

6. Sillimanite is a _____________ refractory?

   A. Basic
   B. Neutral
   C. High alumina
   D. Insulating

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

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

8. Pure oxide refractories are generally monocrystalline in nature and are self bonded _______________ bricks are generally used as moderator in nuclear reactors?

   A. Beryllia
   B. Carborundum
   C. Corundum
   D. Thoria

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

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

10. Periclase refractory contains mainly________________?

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