The adiabatic throttling process of a perfect gas is one of constant enthalpy
In which there is a temperature drop
Which is exemplified by a non-steady flow expansion
Which can be performed in a pipe with a constriction
In which there is an increase in temperature
Correct Answer :
C. Which can be performed in a pipe with a constriction
Related Questions
Boiling of liquid is accompanied with increase in the
Vapor pressure
Specific Gibbs free energy
Specific entropy
All (A), (B) and (C)
A refrigerator may be termed as a
Heat pump
Heat engine
Carnot engine
None of these
Heat of formation of an element in its standard state is
0
< 0
> 0
A function of pressure
Which of the following is not an extensive property?
Free energy
Entropy
Refractive index
None of these
The shape of T-S diagram for Carnot Cycle is a
Rectangle
Rhombus
Trapezoid
Circle
For the gaseous phase chemical reaction, C2H4(g) + H2O(g) ↔ C2H5OH(g), the equilibrium conversion does not depend on the
Steam to ethylene ratio
Temperature
Pressure
None of these
The following heat engine produces power of 100,000 kW. The heat engine operates between 800 K and 300 K. It has a thermal efficiency equal to 50% of that of the Carnot engine for the same temperature. The rate at which heat is absorbed from the hot reservoir is
100,000 kW
160,000 kW
200,000 kW
320,000 kW
Standard temperature and pressure (S.T.P.) is
0°C and 750 mm Hg
15°C and 750 mm Hg
0°C and 1 kgf/cm2
15°C and 1 kgf/cm2
Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?
Expansion valve
Condenser
Refrigerator
Compressor
Work done is a
Property of the system
Path function
Point function
State description of a system
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
Gases are cooled in Joule-Thomson expansion, when it is __________ inversion temperature.
Below
At
Above
Either 'b' or 'c'
On opening the door of an operating refrigerator kept in a closed room, the temperature of the room will
Increase
Decrease
Remain same
Increase in summer and will decrease in winter
When a gas in a vessel expands, its internal energy decreases. The process involved is
Reversible
Irreversible
Isothermal
Adiabatic
The theoretical minimum work required to separate one mole of a liquid mixture at 1 atm, containing 50 mole % each of n- heptane and noctane into pure compounds each at 1 atm is
-2 RT ln 0.5
-RT ln 0.5
0.5 RT
2 RT
The extensive properties are
Volume, mass and number of moles
Free energy, entropy and enthalpy
Both (A) and (B)
None of these
On a P-V diagram of an ideal gas, suppose a reversible adiabatic line intersects a reversible isothermal line at point A. Then at a point A, the slope of the reversible adiabatic line (∂P/∂V)s and the slope of the reversible isothermal line (∂P/ ∂V)T are related as (where, y = Cp/Cv)
(∂P/∂V)S = (∂P/∂V)T
(∂P/∂V)S = [(∂P/∂V)T]Y
(∂P/∂V)S = y(∂P/∂V)T
(∂P/∂V)S = 1/y(∂P/∂V)T
Gibbs phase rule finds application, when heat transfer occurs by
Conduction
Convection
Radiation
Condensation
In the equation, PVn = constant, if the value of n = 1, then it represents a reversible __________ process.
Isothermal
Isobaric
Polytropic
Adiabatic
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
For a stable phase at constant pressure and temperature, the fugacity of each component in a binary system __________ as its mole fraction increases.
Decreases
Increases
Remain same
Decreases linearly
Pick out the wrong statement.
Surface tension of a substance vanishes at critical point, as there is no distinction between liquid and vapour phases at its critical point
Entropy of a system decreases with the evolution of heat
Change of internal energy is negative for exothermic reactions
The eccentric factor for all materials is always more than one
The work done in an adiabatic change in a particular gas depends upon changes in the __________ only.
Temperature
Specific heat
Volume
Pressure
Normal temperature and pressure (N.T.P.) corresponds to
0°C and 760 mm Hg
15°C and 760 mm Hg
20°C and 760 mm Hg
0°C and 1 kgf/cm2
Specific heat of a gas for a reversible adiabatic process is
Negative
Zero
Infinity
None of these
The work done in isothermal compression compared to that in adiabatic compression will be
Less
More
Same
More or less depending upon the extent of work done
The melting point of paraffin wax (which contracts on solidification) __________ with pressure rise.
Increases
Decreases
Remains unchanged
Decreases linearly
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)
For an ideal liquid solution, which of the following is unity?
Activity
Fugacity
Activity co-efficient
Fugacity co-efficient
The number of degrees of freedom at the triple point of water is
0
1
2
3