Which of the following units is not present in both the vapor compression refrigeration system and absorption refrigeration system?
Expansion valve
Condenser
Refrigerator
Compressor
Correct Answer :
D. Compressor
Related Questions
Boiling of liquid is accompanied with increase in the
Vapor pressure
Specific Gibbs free energy
Specific entropy
All (A), (B) and (C)
Heat of reaction at constant volume is identified with __________ change.
Enthalpy
Internal energy
Either (A) or (B)
Neither (A) nor (B)
A two stage compressor is used to compress an ideal gas. The gas is cooled to the initial temperature after each stage. The intermediate pressure for the minimum total work requirement should be equal to the __________ mean of P1 and P2. (where, P1 and P2 are initial and final pressures respectively)
Logarithmic
Arithmetic
Geometric
Harmonic
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
For an ideal solution, the value of activity co-efficient is
0
1
< 1
> 1
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
After throttling, gas temperature
Decreases
Increases
Remain same
May increase or decrease; depends on the nature of the gas
Which of the following processes cannot be made reversible even under ideal condition of operation?
Free expansion of a gas
Compression of air in a compressor
Expansion of steam in a turbine
All (A), (B) & (C)
The first law of thermodynamics is a statement of conservation of
Heat
Momentum
Energy
Work
No work is done by the system, when a reaction occurs at constant
Volume
Temperature
Pressure
None of these
The temperature at which both liquid and gas phases are identical, is called the __________ point.
Critical
Triple
Freezing
Boiling
Van Laar equation deals with the activity coefficients in
Binary solutions
Ternary solutions
Azeotropic mixture only
None of these
Generation of heat by friction is an example of a/an __________ change.
Isothermal
Irreversible
Adiabatic
Reversible
Joule-Thomson co-efficient depends on the
Pressure
Temperature
Both (A) & (B)
Neither (A) nor (B)
Free energy, fugacity and activity co-efficient are all affected by change in the temperature. The fugacity co-efficient of a gas at constant pressure ____with the increase of reduced temperature.
Decreases
Increases
Remains constant
Decreases logarithmically
Pressure-enthalpy chart is useful in refrigeration. The change in internal energy of an ideal fluid used in ideal refrigeration cycle is
Positive
Negative
Zero
Infinity
Pick out the wrong statement.
System (of partially miscible liquid pairs), in which the mutual solubility increases with rise in temperature, are said to possess an upper consolute temperature
Systems, in which the mutual solubility increases with decrease in temperature, are said to possess lower consolute temperature
Nicotine-water system shows both an upper as well as a lower consolute temperature, implying that they are partially miscible between these two limiting temperatures
None of these
If an ideal solution is formed by mixing two pure liquids in any proportion, then the __________ of mixing is zero
Enthalpy
Volume
Both 'a' & 'b'
Neither 'a' nor 'b'
Joule-Thomson co-efficient is defined as
μ = (∂P/∂T)H
μ = (∂T/∂P)H
μ = (∂E/∂T)H
μ = (∂E/∂P)H
When dilute aqueous solutions of two salts are mixed, the process is associated with
Decrease in temperature
Increase in temperature
No change in temperature
Change in temperature which is a function of composition
Extensive properties of a thermodynamic system depend upon the __________ of the system.
Specific volume
Temperature
Mass
Pressure
The value of Cp & Cv respectively for monatomic gases in Kcal/kg Mole.°K are
5 & 3
3.987 & 1.987
1.987 & 0.66
0.66 & 1.987
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
Activity co-efficient is a measure of the
Departure from ideal solution behaviour
Departure of gas phase from ideal gas law
Vapour pressure of liquid
None of these
For a real gas, the chemical potential is given by
RT d ln P
RT d ln f
R d ln f
None of these
Co-efficient of performance for a reversed Carnot cycle working between temperatures T1 and T2 (T1 > T2) is
T2/(T1 - T2)
T1/(T1 - T2)
(T1 - T2)/T1
(T1 - T2)/T2
Pick out the wrong statement.
Trouton's ratio of non-polar liquids is calculated using Kistyakowsky equation
Thermal efficiency of a Carnot engine is always less than 1
An equation relating pressure, volume and temperature of a gas is called ideal gas equation
None of these
(∂T/∂P)H is the mathematical expression for
Specific heat at constant pressure (Cp)
Specific heat at constant volume (Cv)
Joule-Thompson co-efficient
None of these
Work done is a
Property of the system
Path function
Point function
State description of a system
In jet refrigerators, the refrigerating fluid is practically always
Water
Ammonia
Freon
Brine