A. Quartz
B. Cristobalite
C. Tridymite
D. All have the same specific gravity
Related Mcqs:
- Semi-silica bricks compared to silica bricks have_______________?
A. Less fusion point
B. Better spalling resistance
C. Both A. and B.
D. Neither A. not B. - Which is the most stable crystalline form of silica at room temperature ?
A. Quartz
B. Cristobalite
C. Tridymite
D. None of these - Which is the stable form of silica upto 1470°C ?
A. Quartz
B. Cristobalite
C. Tridymite
D. None of these - Which is the stable form of silica below 870°C ?
A. Tridymite
B. Cristobalite
C. Quartz
D. None of these - Which is the stable form of silica between 1470°C and the melting point 1713°C ?
A. Cristobalite
B. Tridymite
C. Quartz
D. None of these - Silica bricks are attacked by basic slags at high temperature. Which of the following is not used solely as a binding material ?
A. Aluminium phosphate
B. Water
C. Lime
D. Plaster of Paris - With increase in the density of silica refractories, its_______________?
A. Resistance to slag attack increases
B. Spalling resistance reduces
C. Both A. and B.
D. Neither A. nor B. - Refractoriness of a typical silica brick corresponds to Segar cone number, ’32’, which is equivalent to a temperature of _____________ °C?
A. 1380
B. 1520
C. 1710
D. 1915 - Addition of zircon to silica refractory brick improves its_____________________?
A. Crushing strength
B. Resistance to slag attack
C. Both A. and B.
D. Neither A. nor B. - Silica bricks are never used for lining the____________________?
A. Beehive coke ovens
B. By-product coke ovens
C. Dome of blast furnace stoves
D. Roof of open hearth furnace
