A. Decarburising
B. Alloying with cobalt
C. Purification
D. Alternate heating & cooling
Related Mcqs:
- The temperature at which the magnetic property of iron disappears (i.e., it becomes nonmagnetic) and its electrical conductivity & specific heat also changes, is called the ‘Curie point’, which is ________________ °C ?
A. 768
B. 908
C. 1400
D. 1539 - Addition of small amount of ________________ to grey cast iron is done to produce nodular grey cast iron ?
A. Manganese
B. Phosphorous
C. Magnesium
D. Chromium - Addition of silicon to cast iron ___________________?
A. Promotes graphite module formation
B. Improves its ductility
C. Does not promote graphite flakes formation
D. Increases the fluidity of molten metal - The main reducing agent in iron blast furnace is____________________?
A. Carbon dioxide
B. Carbon monoxide
C. Oxygen
D. Air - Eutectic reaction for iron-carbon system occurs at a temperature of _______________ °C ?
A. 723
B. 959
C. 1147
D. 1493 - Iron & manganese present in the polluted water is removed by __________________?
A. Simple filtration
B. Oxidation followed by settling & filtration
C. Chemical coagulation
D. Chlorination only - Oceans act as sinks for atmospheric gases including carbon dioxide whose concentration in the atmosphere is increased by the_______________?
A. Forestation
B. Rain
C. Green house effect
D. Vegetation - The chemical potential of a component (μi) of a phase is the amount by which its capacity for doing all work, barring work of expansion is increased per unit amount of substance added for an infinitesimal addition at constant temperature and pressure. It is given by_________________?
A. (∂E/∂ni)S, v, nj
B. (∂G/∂ni)T, P, nj = (∂A/∂ni) T, v, nj
C. (∂H/∂ni)S, P, nj
D. All (A), B. and (C) - The freezing point of a liquid decreases when the pressure is increased, if the liquid ____________ while freezing?
A. Contracts
B. Expands
C. Does not change in volume
D. Either (A), B. or (C) - The temperature of a gas in a closed container is 27° C. If the temperature of the gas is increased to 300° C, then the pressure exerted is___________________?
A. Doubled
B. Halved
C. Trebled
D. Unpredictable
