A. Reduced by the addition of acid oxides
B. Increased by the addition of acid oxides
C. Not affected by the addition of acid oxides
D. Always less than 1000°C
Related Mcqs:
- 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 - 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 - Which is not a basic refractory ?
A. Chrome magnesite
B. Magnesite
C. Dolomite
D. Silicon carbide - Which is a basic refractory ?
A. Fireclay
B. Silica
C. Chrome magnesite
D. None of these - Highest melting (m.p = 3070°C) oxide refractory is__________________?
A. Alumina
B. Thoria
C. Zirconia
D. Magnesia - Mixing of ground refractory material and water is done in a ______________ mill?
A. Pug
B. Ball
C. Tube
D. Rod - High thermal conductivity of a refractory material is not important, when it is to be used in the______________________?
A. Coke oven regenerators
B. Muffle furnace
C. Blast furnace
D. Recuperators - 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 - 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 - Which of the following is not a high alumina refractory material ?
A. Kyanite
B. Sillimanite
C. Diaspore
D. Periclase
