Which is not an acidic refractory ?

Related Mcqs:

1. Fusion point of an acidic refractory material is________________?

   A. Increased by the addition of basic oxides
   B. Reduced by the addition of basic oxides
   C. Not affected by the addition of basic oxides
   D. Always more than 2500°C

2. Which of the following is not an acidic refractory?

   A. Silica bricks
   B. Fireclay bricks
   C. Bauxite bricks
   D. Magnesia bricks

3. Which is an acidic refractory ?

   A. Magnesite
   B. Dolomite
   C. Fireclay
   D. Chrome magnesite

4. 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

5. 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

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

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

7. Spalling resistance of a refractory cannot be increased by ____________________?

   A. Increasing its porosity
   B. Using a coarser grog during its manufacture
   C. Decreasing its thermal co-efficient of expansion
   D. Making it denser

8. Periclase refractory contains mainly________________?

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

9. Pyrometric cone equivalent (PCE) of a refractory is the measure of its_________________?

   A. Spalling resistance
   B. Fusion point
   C. Resistance to slag penetration
   D. Resistance to carbon monoxide attack

10. Thermal conductivity of refractory bricks_________________?

    A. Increases with decrease in porosity
    B. Decreases with decreases in porosity
    C. Is independent of its porosity and is maximum for insulating bricks
    D. Increases with the amount of air entrapped in pores