197. The purpose of coke in the charge for blast furnace is
A.To act as an aggregate of iron-bearing mineral
B.To form a slag by combining with impurities
C.To supiily heat to reduce ore and melt the iron
D.To control the grade of cast iron produced

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198. The quantity of lime required in a cupola for production of 1 tonne of casting is of the order of
A.30 kg
B.50 kg
C.100 kg
D.300 kg

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199. Lime stone is added in blast furnace to flux
A.MnO2
B.SiO2
C.Carbon
D.NH3

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200. The purpose of lime in the charge for blast furnace is
A.To act as an aggregate of iron-bearing mineral
B.To form a slag by combining with impurities
C.To control the grade of iron produced
D.To supply heat to reduce ore and melt the iron

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201. Coal used in cupola is
A.Coke
B.Coal dust
C.Charcoal
D.Pulverised coal

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202. The significance of the yellow flame during the operation of the bessemer converter is
A.That air is burning out the silicon and manganese resulting in high increase in temperature and scrap steel needs to be added to control temperature
B.That silicon has burned out and carbon has started burning
C.That the converter must be tilted and air turned off, otherwise iron would oxidise
D.Yellow flame does not occur in operation of bessemer converter

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203. The quantity of coke required in a cupola for production of 1 tonne of casting is of the order of
A.30 kg
B.300 kg
C.700 kg
D.1000 kg

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