2020. The softest material just next to talc in the Mhos scale is
Quartz
Gypsum
Feldspar
Fluorite
✅ The correct answer is option B.
2022. Which metal is protected by the layer of its own oxide?
Iron
Silver
Calcium
Aluminium
✅ The correct answer is option D.
2024. Invar contains the highest percentage of
Vanadium
Iron
Tungsten
Cobalt
✅ The correct answer is option B.
2026. Which of the following would not be a suitable material of construction for handling aqueous hydrofluoric acid (HF) at 100°C ?
Monel
Stainless steel
Graphite
Kel-F and teflon
✅ The correct answer is option B.
2028. Combination of metals and ceramics are called
Metalloy
Cermets
Pellets
Non-crystalline ceramics
✅ The correct answer is option B.
1990. Bog iron used for the adsorption of H?S from coke oven gas is
An intimate mixture of saw dust and iron dust (i.e. moist ferric hydroxide)
Iron impregnated with resin (usually bakelite)
Carbon free iron
None of these
✅ The correct answer is option A.
1992. Coke oven regenerators are made of __________ bricks.
Fire clay
Silica
Low thermal conductivity
High electrical conductivity
✅ The correct answer is option A.
1995. The electrical conductivity of a __________ decreases with rise in temperature.
Metal/alloy
Semi-conductor
Dielectric
None of these
✅ The correct answer is option A.
1998. A hardened steel essentially contains
Sorbite
Troostite
Martensite
None of these
✅ The correct answer is option C.
2001. A material capable of undergoing large permanent deformation, when subjected to tension is termed as
Friable
Ductile
Brittle
None of these
✅ The correct answer is option B.