239. The unit of energy in S.I. units is
A.Watt
B.Joule
C.Joule/s
D.Joule/m

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240. According to Gay-Lussac law for a perfect gas, the absolute pressure of given mass varies directly as
A.Temperature
B.Absolute
C.Absolute temperature, if volume is kept constant
D.Volume, if temperature is kept constant

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241. An ideal gas as compared to a real gas at very high pressure occupies
A.More volume
B.Less volume
C.Same volume
D.Unpredictable behaviour

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242. Gas laws are applicable to
A.Gases as well as vapours (P = pressure, V = Volume, T = Temperature, in = mass, R = gas constant, J = Joule's coefficient, Cp = specific heat at constant pressure, C? = specific heat at constant volume, C and n = constant)
B.Gases alone and not to vapours
C.Gases and steam
D.Gases and vapours under certain conditions

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243. According to Dalton's law, the total pressure of the mixture of gases is equal to
A.Greater of the partial pressures of all
B.Average of the partial pressures of all
C.Sum of the partial pressures of all
D.Sum of the partial pressures of all divided by average molecular weight

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244. Which of the following can be regarded as gas so that gas laws could be applicable, within the commonly encountered temperature limits.
A.02, N2, steam, CO2
B.O2, N2, water vapour
C.SO2, NH3, CO2, moisture
D.O2, N2, H2, air

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245. The unit of pressure in S.I. units is
A.Kg/cm2
B.Mm of water
C.Pascal
D.Dynes per square cm

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