1 )
Two moles of an ideal gas at 1 atm are compressed to 2 atm at 273 K . The
enthalpy change of the process will : -
A ) increased , B
) decreased ,
C ) remain same , D
) None of these ,
Correct
Answer : - C ) remain same ,
Explanation
: -
Compression of an ideal gas do not involve change in
enthalpy . So enthalpy change will be zero or remain same .
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2 )
Rate of diffusion of a gas is proportional to : - √ ( P / d ) .
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3 ) The
ratio of most probable velocity to that of average velocity is : -
Solution
: -
The
most probable velocity = Vmps = √ ( 2RT / M )
.
Average velocity = Vavg = √ ( 8RT / Ï€M ) .
So , Vmps / Vavg = √ ( 2RT / M ) / √ ( 8RT / Ï€M
) ,
Vmps / Vavg = √ ( 2 Ï€ / 8 ) = √ Ï€ / 2 , Answer .
OR
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4 )
The factor possible for lower mercury level in capillary tube is : -
A ) high density , B
) low density ,
C ) high pressure , D
) None of these ,
Correct
Answer : - A ) high density ,
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