A gas performs the maximum work, when it expands
Non-uniformly
Adiabatically
Isobarically
Isothermally
Correct Answer :
C. Isobarically
Related Questions
Those solutions in which there is no volume change upon mixing the components in the liquid state and which, when diluted do not undergo any heat change (i.e. heat of dilution is zero), are called __________ solutions.
Ideal
Real
Isotonic
None of these
A cyclic engine exchanges heat with two reservoirs maintained at 100 and 300°C respectively. The maximum work (in J) that can be obtained from 1000 J of heat extracted from the hot reservoir is
349
651
667
1000
A/an __________ system is exemplified by a vessel containing a volatile liquid in contact with its vapor.
Isolated
Closed
Open
None of these
Internal energy of an ideal gas
Increases with increase in pressure
Decreases with increase in temperature
Is independent of temperature
None of these
Throttling (Joule-Thomson effect) process is a constant __________ process.
Enthalpy
Entropy
Pressure
None of these
As pressure approaches zero, the ratio of fugacity to pressure (f/P) for a gas approaches
Zero
Unity
Infinity
An indeterminate value
Fugacity and pressure are numerically not equal for the gases
At low temperature and high pressure
At standard state
Both (A) and (B)
In ideal state
Pick out the wrong statement.
A closed system does not permit exchange of mass with its surroundings but may permit exchange of energy.
An open system permits exchange of both mass and energy with its surroundings
The term microstate is used to characterise an individual, whereas macro-state is used to designate a group of micro-states with common characteristics
None of the above
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)
If two gases have same reduced temperature and reduced pressure, then they will have the same
Volume
Mass
Critical temperature
None of these
Consider the reaction, C + O2 CO2; ΔH = - 94 kcal. What will be the value of ΔH for the reaction CO2 → C + O2?
-94 kcal
+94 kcal
> 94 kcal
< -94 kcal
In case of an __________ process, the temperature of the system increases.
Isothermal compression
Isothermal expansion
Adiabatic expansion
Adiabatic compression
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
The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances. This is the
Lewis-Randall rule
Statement of Van't Hoff Equation
Le-Chatelier's principle
None of these
Joule-Thomson co-efficient depends on the
Pressure
Temperature
Both (A) & (B)
Neither (A) nor (B)
Near their critical temperatures, all gases occupy volumes __________ that of the ideal gas.
Less than
Same as
More than
Half
Van Laar equation deals with the activity coefficients in
Binary solutions
Ternary solutions
Azeotropic mixture only
None of these
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
If the pressure on 100 c.c. of air is halved, then its volume (at the same temperature) would be __________ c.c.
100
50
205
200
Lenz's law results from the law of conservation of
Mass
Momentum
Energy
None of these
A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. Specific heat of block material is 0.4 kJ.kg-1. K-1. Ignoring the effect of expansion and contraction and also the heat capacity to tank, the total entropy change in kJ.kg-1, K-1 is
-1.87
0
1.26
3.91
In an ideal solution, the activity of a component equals its
Mole fraction
Fugacity at the same temperature and pressure
Partial pressure
None of these
Specific volume of an ideal gas is
Equal to its density
The reciprocal of its density
Proportional to pressure
None of these
Equilibrium constant of a reaction varies with the
Initial concentration of the reactant
Pressure
Temperature
None of these
Claude's liquefaction process employs the cooling of gases by
Expansion in an engine
Following a constant pressure cycle
Throttling
None of these
The principle applied in liquefaction of gases is
Adiabatic expansion
Joule-Thomson effect
Both (A) and (B)
Neither (A) nor (B)
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
Compressibility factor for almost all the gases are approximately same at the same
Pressure and temperature
Reduced pressure and reduced temperature
Critical pressure and critical temperature
None of these
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 heat capacities for the ideal gas state depend upon the
Pressure
Temperature
Both (A) & (B)
Neither (A) nor (B)