Choose the condition that must be specified in order to liquify CO2 (triple point for CO2 is - 57°C and 5.2 atm).
Pressure must be kept below 5.2 atm
Temperature must be kept above - 57°C
Pressure must be kept below 5.2 atm. and temperature must be kept above 57°C
Pressure and temperature must be kept below 5.2 atm. and - 57°C respectively
Correct Answer :
D. Pressure and temperature must be kept below 5.2 atm. and - 57°C respectively
Related Questions
Specific volume of an ideal gas is
Equal to its density
The reciprocal of its density
Proportional to pressure
None of these
Compound having large heat of formation is
More stable
Less stable
Not at all stable (like nascent O2)
Either more or less stable; depends on the compound
The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called the __________ temperature.
Critical
Boyle
Inversion
Reduced
In the equation, PVn = constant, if the value of n = ± ∞, then it represents a reversible __________ process.
Adiabatic
Isometric
Isentropic
Isothermal
If atmospheric temperature and dew point are nearly equal, then the relative humidity is
Zero
50%
Almost 100%
unpredictable
Dry ice is
Moisture free ice
Solid helium
Solid carbon dioxide
None of these
For an ideal gas, the activity co-efficient is
Directly proportional to pressure
Inversely proportional to pressure
Unity at all pressures
None of these
Dryness fraction of wet steam is defined as the ratio of mass of vapour in the mixture to the mass of mixture __________ calorimeter is not used for measuring the dryness fraction of steam.
Bomb
Separating
Bucket
Throttling
In vapour compression refrigeration system, if the evaporator temperature and the condenser temperatures are -13°C and 37°C respectively, the Carnot COP will be
5.2
6.2
0.168
Data insufficient, can't be found out
Efficiency of a Carnot engine working between temperatures T1 and T2 (T1 < T) is
(T2 - T1)/T2
(T2 - T1)/T1
(T1 - T2)/T2
(T1 - T2)/T1
Joule-Thomson co-efficient which is defined as, η = (∂T/∂P)H = 1/Cp (∂H/∂T)P, changes sign at a temperature known as inversion temperature. The value of Joule-Thomson co-efficient at inversion temperature is
0
∞
+ve
-ve
One ton of refrigeration is defined as the heat rate corresponding to melting of one ton of ice in one
Hour
Day
Minute
Second
Joule-Thomson co-efficient for a perfect gas is
Zero
Positive
Negative
None of these
__________ Equation predicts the activity coefficient from experimental data.
Lewis-Randall
Margules
Van Laar
Both (B) & (C)
The standard Gibbs free energy change of a reaction depends on the equilibrium
Pressure
Temperature
Composition
All (A), (B) and (C)
The energy of activation of exothermic reaction is
Zero
Negative
Very large compared to that for endothermic reaction
Not possible to predict
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
In the equation PVn = constant, if the value of n = y = Cp/Cv, then it represents a reversible __________ process.
Isothermal
Adiabatic
Isentropic
Polytropic
The internal energy of an ideal gas does not change in a reversible __________ process.
Isothermal
Adiabatic
Isobaric
Isometric
Which of the following non-flow reversible compression processes require maximum work?
Adiabatic process
Isothermal process
Isobaric process
All require same work
(1/V) (∂V/∂T)P is the mathematical expression
Joule-Thomson co-efficient
Specific heat at constant pressure (Cp)
co-efficient of thermal expansion
Specific heat at constant volume (CV)
Choose the condition that must be specified in order to liquify CO2 (triple point for CO2 is - 57°C and 5.2 atm).
Pressure must be kept below 5.2 atm
Temperature must be kept above - 57°C
Pressure must be kept below 5.2 atm. and temperature must be kept above 57°C
Pressure and temperature must be kept below 5.2 atm. and - 57°C respectively
In the decomposition of PCl5 represented by, PCl5 PCl3 + Cl2, decrease in the pressure of the system will __________ the degree of dissociation of PCl5.
Increase
Decrease
Not alter
None of these
Heating of water under atmospheric pressure is an __________ process.
Isochoric
Isobaric
Adiabatic
Isothermal
Ideal refrigeration cycle is
Same as Carnot cycle
Same as reverse Carnot cycle
Dependent on the refrigerant's properties
The least efficient of all refrigeration processes
If heat contents of CH4, C2H4 and C3H8 are -17.9, 12.5 and -24.8 kcal/mole respectively, than ΔH for the reaction CH4(g) + C2H4(g) C3H8(g) will be __________ Kcal.
-19.4
-30.2
55.2
-55.2
__________ explains the equilibrium constant for any chemical reaction.
Henry's law
Law of mass action
Hess's law
None of these
The gas law (PV = RT) is true for an __________ change.
Isothermal
Adiabatic
Both (A) & (B)
Neither (A) nor (B)
(∂E/∂T)V is the mathematical expression for
CV
Enthalpy change
Free energy change
None of these
Gibbs-Duhem equation relates composition in liquid phase and the __________ at constant temperature & pressure.
Fugacity
Partial pressure
Activity co-efficient
All (A), (B), and (C)