The specific heat of saturated water vapour at 100°C is
∞
-ve
0
+ve
Correct Answer :
B. -ve
Related Questions
For a cyclic process, a fixed ratio between heat and work
Always exists
May exist
Never exists
Is difficult to predict
It is desired to bring about a certain change in the state of a system by performing work on the system under adiabatic conditions.
The amount of work needed is path dependent
Work alone cannot bring out such a change of state
The amount of work needed is independent of path
More information is needed to conclude anything about the path dependence or otherwise of the work needed
Pick out the wrong statement.
Minimum number of degree of freedom of a system is zero
Degree of freedom of a system containing a gaseous mixture of helium, carbon dioxide and hydrogen is 4
For a two phase system in equilibrium made up of four non-reacting chemical species, the number of degrees of freedom is 4
Enthalpy and internal energy change is zero during phase change processes like melting, vaporisation and sublimation
The first law of thermodynamics is a restatement of the law of conservation of
Mass
Energy
Momentum
None of these
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
The change in __________ is equal to the reversible work for compression in steady state flow process under isothermal condition.
Internal energy
Enthalpy
Gibbs free energy
Helmholtz free energy
The efficiency of a Carnot heat engine operating between absolute temperatures T1 and T2 (when, T1 > T2) is given by (T1 - T2)/T1. The co-efficient of performance (C.O.P.) of a Carnot heat pump operating between T1 and T2 is given by
T1/(T1-T2)
T2/(T1-T2)
T1/T2
T2/R1
Trouton's ratio of __________ liquids is calculated using Kistyakowsky equation.
Polar
Non-polar
Both (A) & (B)
Neither (A) nor (B)
Free energy change of mixing two liquid substances is a function of the
Concentration of the constituents only
Quantities of the constituents only
Temperature only
All (A), (B) and (C)
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
The entropy change in a reversible isothermal process, when an ideal gas expands to four times its initial volume is
R loge 4
R log10 4
Cv log10 4
Cv loge 4
Number of components (C), phase (P) and degrees of freedom (F) are related by Gibbs phase rule as
P + F - C = 2
C = P - F + 2
F = C - P - 2
P = F - C - 2
When a gas is expanded from high pressure region to low pressure region; temperature change occurs. This phenomenon is related to the
Gibbs-Duhem equation
Gibbs-Helmholtz equation
Third law of thermodynamics
Joule-Thomson effect
Internal energy change of a system over one complete cycle in a cyclic process is
Zero
+ve
-ve
Dependent on the path
For a single component two phase mixture, the number of independent variable properties are
Two
One
Zero
Three
For organic compounds, group contribution method can be used for the estimation of
Critical properties
Specific gravity
Specific volume
Thermal conductivity
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
Keeping the pressure constant, to double the volume of a given mass of an ideal gas at 27°C, the temperature should be raised to __________ °C.
270
327
300
540
When liquid and vapour phase of multi-component system are in equilibrium (at a given temperature and pressure), then chemical potential of each component is
Same in both the phases
Zero in both the phases
More in vapour phase
More in liquid phase
The compressibility factor of a gas is given by (where, V1 = actual volume of the gas V2 = gas volume predicted by ideal gas law)
V1/V2
V2/V1
V1 - V2
V1.V2
With increase in reduced temperature, the fugacity co-efficient of a gas at constant reduced pressure
Increases
Decreases
Remain same
Decreases linearly
Which of the following exemplifies an adiabatic process?
Melting of ice
Condensation of alcohol vapor
Sudden bursting of a cycle tube
Evaporation of water
Trouton's ratio is given by (where λb, = molal heat of vaporisation of a substance at its normal boiling point, kcal/kmol Tb = normal boiling point, °K)
λb/Tb
Tb/λb
√(λb/Tb)
√(Tb/λb)
In the reaction, represented by, 2SO2 + O2 2SO3; ΔH = - 42 kcal; the forward reaction will be favoured by
Low temperature
High pressure
Both (A) and (B)
Neither (A) nor (B)
Compressibility factor (i.e., the ratio of actual volume of gas to the volume predicted by ideal gas law) for all gases are
Always greater than one
Same at the same reduced temperature
Same at the same reduced pressure
Both (B) & (C)
The internal energy of an ideal gas is a function of its __________ only.
Molecular size
Volume
Pressure
Temperature
Entropy is a/an
State function
Macroscopic property
Extensive property
None of these
Throttling process is a/an __________ process.
Reversible and isothermal
Irreversible and constant enthalpy
Reversible and constant entropy
Reversible and constant enthalpy
For a thermodynamic system containing 'x' chemical species, the maximum number of phases that can co-exist at equilibrium is
x
x + 1
x + 2
x + 3
In the reaction, H2 +I2 2HI, addition of an inert gas will
Increase the partial pressure of H2
Increase the partial pressure of I2
Increase the total pressure and hence shift the equilibrium towards the right
Not affect the equilibrium conditions