It is decided to verify boyle’s law over a wide range of pressure and temperature. The most suitable gas to be selected for this purpose is
Oxygen
Hydrogen
Helium
Air
Gay-lussac stipulates that
p1v2=p2v2 at constant temperature
at constant pressure
at constant volume
pv=mRT
For all perfect gases, the change in volume is 1/273 of original volume at 0oC for every 1oC change in temperature while pressure remains constant. This statement is referred to as
Boyle’s law
Charle’s law
Gay-lussac’s law
Joule’s law
The characteristic gas equation pv=mRT is essentially valid for a
Real gas
Perfect gas
Monoatomic gas
Mixture of gases
In the characteristic gas equation pv=mRT, the gases constant for air has the value
29.27 mkgf/kg/oK
287 mkgf/kg/oK
427 mkgf/kg/oK
848 mkgf/kg/oK
Which one of the following identity is correct?
G=MR
G=M/R
G=R/M
G=M2R
Where G is universal gas constant. R is characteristic gas constant and M is the molecular weight
The value of universal gas constant is
427 mkgf/kg mole/oK
735 mkgf/kg mole/oK
848 mkgf/kg mole/oK
8314 mkgf/kg mole/oK
Which one of the following gases will have the maximum value of gas constant R?
Nitrogen
Carbon dioxide
Sulpur dioxide
Oxygen
Indicate, the correct relation between the gas constant R, the joule’s mechanical equaivalent of heat j, the adiabatic exponent y and the specific heat at constant volume; cv=
The specific heat of gas remains constant at all pressures and temperatures. This statement pertains to
Joule’s law
Regnault’s law
Avogadro’s law
Maxwell law
The specific heats of an ideal gas depend on its
Temperature
Pressure
Volume
Molecular weight and structure
Which aspect is true in the context of avogadro’s hypothesis?
The product of molecular weight and the characteristic gas constant is same for all gases
The pressure of a gas mixture equals the sum of partial pressures of the gases comprising the mixture
For a gas, the specific heat at constant pressure is greater than the specific heat at constant volume
The molecular weight of all gases occupy the same volume under same conditions of pressure and temperature
For most of the gases at given temperature and pressure, the mole has a constant value of the parameter.
Enthalpy
Internal energy
Volume
Mass
The molecular weight expressed in gm, i.e., one gm mole of all gases at normal temperature and pressure occupies a volume equal to
29.27 liters
22.4 liters
42.7 liters
84.8 liters
The internal energy of a perfect gas does not change during
Adiabatic process
Isobaric process
Isothermal process
Isochoric process
Two gases having molecular weights 32 and 28 expand at constant pressure through the same temperature range. The ratio of work done by the two gases will be
7:8
8:7
7:6
3:2
Two vessels of the same volume capacity V contain gases A and B at the same pressure P. when the two vessels are connected together by a small tube and constant temperature conditions prevail, then resultant pressure will be
P/2
P
2P
4P
Gas laws are least valid in case of
Mono-atomic gases
Real gases
Vapours
Mixture of gases
The ideal gas laws can be applied, with least error, to
Boiling water
Wet steam
Dry saturated steam
Superheated steam
The law PV=mRT is obeyed most closely by a real gas under conditions of
High pressure and high temperature
Low pressure and low temperature
Low pressure and high temperature
High pressure and low temperature
The temperature at which a real gas obeys the ideal gas laws over a wide range of pressure is called
Boyle’s temperature
Reduced temperature
Critical temperature
Triple point temperature
In the van der waal’s equation
(p+1/v2)(v-b)=RT
the constant accounts for
The finite volume occupied by the gas molecules
The molecular forces of attraction
The elastic collision between the gas molecules
The momentum of gas molecules in random fashion
In the general gas equation pv=RT, van der waal introduced a correction factor a/v2 which is added to pressure p. this factor a/v2 represents
Mean velocity of the gas molecules
Attraction force between molecules
Volume occupied by the molecules
Effective area of the molecules
In the van der waal’s equation
(p+1/v2)(v-b)=RT,
the units of constant a are:
Nm2
N/M4
Nm4
None of the above
In the van der waal’s equation
(p+1/v2)(v-b)=RT,
a greater value of constant a indicates
Higher density of the gas
Less force of cohesion
Closeness of the gas to the ideal conditions
That the gas can be liquefied easily
Which of the following statements about van der waal’s equation is valid?
Valid for all pressures and temperatures
Represents a straight line on pv versus v plot
Has three rootsof identical value at the critical point
Valid for diatomic gases only
The thermodynamic equation for a gas is
pv=m RT
+du
f(p, v, T)=0
pvn=constant
A real gas undergoes an isothermal compression. The net internal energy
Remains the same
Decreases
Increases
Increases by an amount proportional to change in pressure
The relation du=cvdT holds good for
Any gas and constant volume processes
Any gas and all processes
An ideal gas the all processes
Gas, vapour and all processes
For liquefaction of a gas, the favourable conditions are:
Low temperature and low pressure
Low temperature and high pressure
Low temperature and a catalyst
High temperature and low pressure
Which parameter remains constant during joule-thomson expansion?
Temperature
Pressure
Enthalpy
Volume
Critical temperature of a gas is the temperature
At which the intermolecular gap is reduced to zero
At which its liquefaction just starts
At which its liquefaction is complete
Above which it can not be liquefied
Identify the theoretical equation of state which is derived form kinetic theory or statistical thermodynamics
Berthelot equation
Viral equation
Clausius equation
Dieterici equation
Which of the following equations has more than two constants (a part form the characteristic gas constant R)?
Berthelot equation
Van der waal’s equation
Beattie bridgeman equation
Redlich and kwong equation
Berthelot equation of state has the same form as van der waal equation. However the constant a is taken to vary as
1/T2
1/T
T
T2
A reduced property is the ratio of property in a given state to the
Maximum value of the property
Minimum value of the property
Value of the property at the critical point
Value of the property at the triple point
For an ideal gas, the compressibility factor is
Zero
Unity
Infinity
Some finite value greater than unity
The compressibility factor at the critical point for the van der waal’s equation is
Unity
2/5
3/8
27/64
All of the following statements are correct except
Reduced pressure is a dimensionless quantity
All gases have compressibility factor of nearly unity at high temperatures and pressures
The van der waal’s equation has three roots of identical values at the critical point
In case of real gases, the deviation from the ideal conditions is maximum when each of the reduced pressure and reduced temperature has unit value
Choose the false statement
Liquid fuels have higher calorific value than solid fuels
A good fuel has a high ignition point
Coal gas consists mainly of hydrogen, carbon monoxide and various hydrocarbons
Calorific value of a gaseous fuel is expressed in kcal/m3
Use of pulverized coal in boiler furnace provides
Smokeless burning
Better combustion
Loss corrosion on furnace walls
High calorific value
Bomb calorimeter is used to determine
Calorific value of solid or liquid fuels
Calorific value of gaseous fuels
Ash content of solid fuels
Incombustible matter in solid fuel
Which of the following constituents of a fuel does not contribute to its calorific value on combustion?
Carbon
Hydrogen
Sulphur
Nitrogen
The percentage by weight of oxygen in atmospheric air is
19
21
23
27
For complete burning of 1 kg of carbon, the air repuired will be about
2.67 kg
11.6 kg
12.7 kg
14.5 kg
High excess air in combustion of fuels will result in
Complete combustion
Smoky exhaust
High calorific value
Increased fuel consumption
Incomplete combustion of fuel is characterized by
High temperature of flue gas
High percentage of oxygen in flue gas
High percentage of carbon dioxide n flue gas
Smoky exhaust
Orsat apparatus is meant for
Volumetric analysis of the flue gas
Direct determination of nitrogen in the flue gas
Finding out the combustion efficiency
Determining the calorific value of gaseous fuels
The sequence of absorotion in the flue gas analysis by Orsat’s apparatus is
CO2, CO and O2
CO2, O2 and CO
O2, CO2 and CO
CO, O2, and CO2
In Orsat apparatus, oxygen is absorbed in
Cupurous chloride
Potassium carbonate
Dilute potassium carbonate
Alkaline solution of pyragollic acid