169. The distillation carried out in such a way that the liquid with the lowest boiling point is first evaporated and recondensed, then the liquid with the next higher boiling point is then evaporated and recondensed, and so on until all the available liquid fuels are separately recovered in the sequence of their boiling points, Such a process is called
A.Cocking
B.Carbonisation
C.Fractional distillation
D.Full distillation

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170. Which of the following statement is incorrect?
A.The liquid fuels consist of hydrocarbons
B.The liquid fuels have higher calorific value than solid fuels
C.The solid fuels have higher calorific value than liquid fuels
D.A geo fuel should have low ignition point

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171. Which of the following gas is mostly used in town for street and domestic lighting and heating?
A.Producer gas
B.Coal gas
C.Mond gas
D.Coke oven gas

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172. The value of gas constant (R) in S.I. units is
A.0.287 J/kgK
B.2.87 J/kgK
C.28.7 J/kgK
D.287 J/kgK

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173. In the first law of thermodynamics, the total energy of the system remains constant
A.TRUE
B.False
C.
D.

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174. The efficiency of Diesel cycle increases with
A.Decrease in cut-off
B.Increase in cut-off
C.Constant cut-off
D.None of these

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175. Coal gas is obtained by mixing coal and gas at ambient conditions
A.Yes
B.No
C.
D.

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