Beryllia (which is used in making crucibles for melting uranium & thorium) is superior to alumina in all respects for high temperature (> 1900°C ) use, except ?

Related Mcqs:

Lessing ring is formed by the addition of a partition across the centre of a raschig ring, which results in an area increase of about ______________ percent?

A. 5 B. 20 C. 35 D. 55...

Grog addition in fireclay during brick manufacture is done to_________________?

A. Reduce its shrinkage on heating B. Impart greater spalling resistance C. Enhance the strength of fired refractories D. All A., B. and C....

Electrical resistor bars are made of _______________?

A. Silicon carbide B. Alumina C. Zirconia D. Graphite...

Dry mix hydraulic compositions of refractory aggregates with suitable bonding materials are called refractory_________________?

A. Mortars B. Cements C. Castables D. None of these...

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

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