Pick out the correct statement:
In an isothermal system, irreversible work is more than reversible work
Under reversible conditions, the adiabatic work is less than isothermal work
Heat, work, enthalpy and entropy are all 'state functions'
Matter and energy cannot be exchanged with the surroundings in a closed system
Correct Answer :
B. Under reversible conditions, the adiabatic work is less than isothermal work
Related Questions
In Joule-Thomson porous plug experiment, the
Enthalpy does not remain constant
Entire apparatus is exposed to surroundings
Temperature remains constant
None of these
Entropy change of mixing two liquid substances depends upon the
Molar concentration
Quantity (i.e. number of moles)
Both (A) and (B)
Neither (A) nor (B)
The co-efficient of performance (COP) of a refrigerating system, which is its index of performance, is defined as the ratio of useful refrigeration to the net work. The units of __________ and COP are the same.
Kinematic viscosity
Work
Temperature
None of these
Pick out the Clausius-Clapeyron equation from the following:
dP/dT = ΔH/TΔV
ln P = - (ΔH/RT) + constant
ΔF = ΔH + T [∂(ΔF)/∂T]P
None of these
The equilibrium constant for a chemical reaction at two different temperatures is given by
Kp2/Kp1 = - (ΔH/R) (1/T2 - 1/T1)
Kp2/Kp1 = (ΔH/R) (1/T2 - 1/T1)
Kp2/Kp1 = ΔH (1/T2 - 1/T1)
Kp2/Kp1 = - (1/R) (1/T2 - 1/T1)
The total change in the enthalpy of a system is independent of the
Number of intermediate chemical reactions involved
Pressure and temperature
State of combination and aggregation in the beginning and at the end of the reaction
None of these
At absolute zero temperature, the __________ of the gas is zero.
Pressure
Volume
Mass
None of these
An isolated system can exchange __________ with its surroundings.
Matter
Energy
Neither matter nor energy
Both matter and energy
The value of Joule-Thomson co-efficient, in case where cooling occurs after the throttling process is
0
∞
+ve
-ve
A closed system is cooled reversibly from 100°C to 50°C. If no work is done on the system
its internal energy (U) decreases and its entropy (S) increases
U and S both decreases
U decreases but S is constant
U is constant but S decreases
Which of the following is Clausius-Clapeyron Equation for vaporisation of an ideal gas under the condition that the molar volume of liquid is negligible compared to that of the vapor?
d ln p/dt = Hvap/RT2
d ln p/dt = RT2/Hvap
dp/dt = RT2/Hvap
dp/dt = Hvap/RT2
The necessary condition for phase equilibrium in a multiphase system of N components is that the
Chemical potentials of a given component should be equal in all phases
Chemical potentials of all components should be same in a particular phase
Sum of the chemical potentials of any given component in all the phases should be the same
None of these
For an ideal gas, the internal energy depends upon its __________ only.
Molecular size
Temperature
Volume
Pressure
Boyle's law for gases states that
P ∝ 1/V, when temperature is constant
P ∝ 1/V, when temperature & mass of the gas remain constant
P ∝ V, at constant temperature & mass of the gas
P/V = constant, for any gas
Which of the following is not an intensive property?
Volume
Density
Temperature
Pressure
A cylinder contains 640 gm of liquid oxygen. The volume occupied (in litres) by the oxygen, when it is released and brought to standard conditions (0°C, 760 mm Hg) will be __________ litres.
448
224
22.4
Data insufficient; can't be computed
A gas performs the maximum work, when it expands
Non-uniformly
Adiabatically
Isobarically
Isothermally
Tea kept in a thermos flask is vigorously shaken. If the tea is considered as a system, then its temperature will
Increase
Decrease
Remain unchanged
First fall and then rise
Solubility of a substance which dissolves with an increase in volume and liberation of heat will be favoured by the
Low pressure and high temperature
Low pressure and low temperature
High pressure and low temperature
High pressure and high temperature
Pick out the wrong statement.
An ideal liquid or solid solution is defined as one in which each component obeys Raoult's law
If Raoult's law is applied to one component of a binary mixture; Henry's law or Raoult's law is applied to the other component also
Henry's law is rigorously correct in the limit of infinite dilution
None of these
For an ideal liquid solution, which of the following is unity?
Activity
Fugacity
Activity co-efficient
Fugacity co-efficient
The unit of fugacity is the same as that of the
Pressure
Temperature
Volume
Molar concentration
The effect of changing the evaporator temperature on COP as compared to that of changing the condenser temperature (in vapour compression refrigeration system) is
Less pronounced
More pronounced
Equal
Data insufficient, can't be predicted
__________ calorimeter is normally used for measuring the dryness fraction of steam, when it is very low.
Bucket
Throttling
Separating
A combination of separating & throttling
Pick out the correct equation relating 'F' and 'A'.
F = A + PV
F = E + A
F = A - TS
F = A + TS
Which of the following is Virial equation of state?
(p + a/V2)(V - b) = nRT
PV = nRT
PV = A + B/V + C/V2 + D/V3 + ...
None of these
The amount of heat required to decompose a compound into its elements is __________ the heat of formation of that compound from its elements.
Less than
More than
Same as
Not related to
The equation Tds = dE - PdV applies to
Single phase fluid of varying composition
Single phase fluid of constant composition
Open as well as closed systems
Both (B) and (C)
When liquid and vapour phases of one component system are in equilibrium (at a given temperature and pressure), the molar free energy is
More in vapour phase
More in liquid phase
Same in both the phases
Replaced by chemical potential which is more in vapour phase
A large iceberg melts at the base, but not at the top, because of the reason that
Ice at the base contains impurities which lowers its melting point
Due to the high pressure at the base, its melting point reduces
The iceberg remains in a warmer condition at the base
All (A), (B) and (C)