A vessel contains 14 gm (7 moles) of hydrogen and 96 gm (3 moles) of oxygen at STP. A chemical reaction is induced by passing electric spark in the vessel till one of the gases is consumed. The temperature is brought back to it's starting value 273 K. The pressure in the vessel is

 

  •   0.1 atm                       

  •   0.2 atm

  •   0.3 atm                       

  •   0.4 atm

A jar contains a gas and few drops of water at T K. The pressure in the jar is 830 mm of mercury. The temperature of jar is reduced by 1%. The saturated vapour pressure of water at the two temperatures are 30 mm and 25 mm of mercury. Then the new pressure in the jar will be

  •   917 mm of Hg                       

  •   717 mm of Hg

  •   817 mm of Hg                       

  •   None of these

Molar specific heat of oxygen at constant pressure CP=7.2 cal/mol°C  and  R=8.3 joule/mol/K. At constant volume, 5 mol of oxygen is heated from 10°C to 20°C, the quantity of heat required is approximately

  •   25 cal                               

  •   50 cal

  •   250 cal                             

  •   500 cal

One mole of an ideal gas requires 207 J heat to raise the temperature by 10 K when heated at constant pressure. If the same gas is heated at constant volume to raise the temperature by the same 10 K, the heat required is

(Given the gas constant R=8.3 J/molK)

  •   198.7 J                 

  •   29 J

  •   215.3 J                 

  •   124 J

The expansion of an ideal gas of mass m at a constant pressure P is given by the straight line D. Then the expansion of the same ideal gas of mass 2m at a pressure P/ 2 is given by the straight line , where number on graphs indicate slope , is- 

  •   E                           

  •   C

  •   B                           

  •   A

An experiment is carried out on a fixed amount of gas at different temperatures and at high pressure such that it deviates from the ideal gas behaviour. The variation of PVRT with P is shown in the diagram. The correct variation will correspond to, (Assuming that the gas in consideration is nitrogen)
 

  • Curve A                             

  •  Curve B

  • Curve C                             

  •  Curve D

The figure below shows the graph of pressure and volume of a gas at two temperatures T1 and T2. Which one, of the following, inferences is correct?

 

  •   T1>T2                                 

  •  T1=T2

  •  T1<T2                                   

  • No inference can be drawn

The expansion of unit mass of a perfect gas at constant pressure is shown in the diagram. Here

  • a = volume, b = °C temperature

  •  a = volume, b = K temperature

  •  a = °C temperature, b = volume

  •  a = K temperature, b = volume

An ideal gas is initially at temperature T and volume V. Its volume increases by V due to an increase in temperature T, pressure remaining constant. The quantity δ=V/VT varies with temperature as

  •  

  •  
  •  
  •  

Pressure versus temperature graph of an ideal gas of equal number of moles of different volumes are plotted as shown in figure. Choose the correct alternative

 

  •  V1=V2 , V3=V4  and V2>V3

  •  V1=V2 , V3=V4  and V2<V3

  •  V1=V2 , V3=V4

  •  V4>V3 > V2>V1

Pressure versus temperature graph of an ideal gas is as shown in figure. Density of the gas at point A is ρ0 . Density at B will be

    

  •   34ρ0                             

  •   32ρ0

  •   43ρ0                             

  •   2 ρ0

Graph of specific heat at constant volume for a monoatomic gas is

 

  •                           

  •  

  •                         

  •  

A fix amount of nitrogen gas (1 mole) is taken and is subjected to pressure and temperature variation. The experiment is performed at high pressure as well as high temperatures. The results obtained are shown in the figures. The correct variation of PV/RT with P will be exhibited by

  •   4                                     

  •   3

  •   2                                     

  •   1

A pressure P - absolute temperature T diagram was obtained when a given mass of gas was heated. During the heating process from the state 1 to state 2 the volume

                   

  • Remained constant                   

  • Decreased

  • Increased                                 

  • Changed erratically

A volume V and pressure P diagram was obtained from state 1 to state 2 when a given mass of a gas is subjected to temperature changes. During this process the gas is

  • Heated continuously

  • Cooled continuously

  • Heated in the beginning and cooled towards the end

  • Cooled in the beginning and heated towards the end

The figure shows the volume V versus temperature T graphs for a certain mass of a perfect gas at two constant pressures of P1 and P2 . What interference can you draw from the graphs

  •  P1 > P2

  •  P1 < P2

  •   P1=P2

  • No interference can be drawn due to insufficient information

From the following P-T graph what interference can be drawn

 

  •  V2 > V1                             

  •  V2 < V1

  •  V2 = V1                             

  • None of the above

Pressure versus temperature graph of an ideal gas at constant volume V of an ideal gas is shown by the straight line A. Now mass of the gas is doubled and the volume is halved, then the corresponding pressure versus temperature graph will be shown by the line

  • A                           

  • B

  • C                         

  •   None of these

Two different isotherms representing the relationship between pressure P and volume V at a given temperature of the same ideal gas are shown for masses m1 and m2 of the gas respectively in the figure given, then

  

  •  m1 > m2                             

  •  m1 = m2

  •  m1 < m2                             

  • None of these

Two different masses m and 3m of an ideal gas are heated separately in a vessel of constant volume, the pressure P and absolute temperature T, graphs for these two cases are shown in the figure as A and B. The ratio of slopes of curves B to A is

 

1.  3 : 1                           

  • 4.  1 : 9

  • 2.  1 : 3

  • 3.  9 : 1                           

  • 4

Under constant temperature, graph between P and 1/V is

  • Straight line             

  • Circle

  • Parabola                   

  • Hyperbola

Volume-temperature graph at atmospheric pressure for a monoatomic gas V in m3, T in °C is

 

  •                       

  •  

  •                         

  •  

At what temperature will the RMS speed of oxygen molecules become just sufficient for escaping from the earth's atmosphere? 
(Given : Mass of oxygen molecule (m) = 2.76 x 10-26 kg, Boltzmann's constant kB = 1.38 × 10-23 J K-1):

  •  2.508×104 K

  •  8.360×104 K

  •  5.016×104 K

  •  1.254×104 K

The molecules of a given mass of gas have RMS. velocity of 200 ms-1 at 27 °C and 1.0x105 Nm-2 pressure. When the temperature and the pressure of the gas are respectively, 127 °C and 0.05x105 Nm-2, the RMS velocity of its molecules in ms-1 is:
  •  4003
  •  10023

  •  1003

  •  1002

One mole of an ideal diatomic gas undergoes a transition from A to B along a path AB as shown in the figure. 
       
The change in internal energy of the gas during the transition is:

  • 20 kJ
  • - 20 kJ
  • 20 J
  • -12 kJ

The ratio of the specific heats CpCv=γ in terms of degrees of freedom(n) is given by:

  •  1+1n
  •  1+n3
  •  1+2n
  •  1+n2
In the given (V–T) diagram, what is the relation between pressure P1 and P2
  • P> P1
  • P< P1
  • Cannot be predicted
  • P= P1
The amount of heat energy required to raise the temperature of 1 g of Helium at NTP, from TK to TK is:

Assertion The molecules of a monoatomic gas have three degrees of freedom. 

Reason The molecules of a diatomic gas have five degrees of freedom.

  1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
  2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
  3. If the assertion is true but the reason is false
  4. If both the assertion and reason are false

Assertion: The molecules of a monatomic gas has three degree of freedom. 
Reason: The molecules of a diatomic gas has five degree of freedom.

  1. If both the assertion and the reason are true and the reason is a correct explanation of the assertion
  2. If both the assertion and reason are true but the reason is not a correct explanation of the assertion
  3. If the assertion is true but the reason is false
  4. If both the assertion and reason are false
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