Chemistry NCERT Exemplar Solutions Class 11th Chapter Five

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Option (i). B only 

For all ideal gas PV = constant. Only B has no change with the change in PV, so only line B represents the curve of ideal gas.

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option (i). Shimla 

The temperature at which the liquid boils when the vapour pressure becomes equal to the atmospheric pressure  is known as the boiling point of the liquid. When the  atmospheric pressure is low, the boiling point of the liquid will be low. As Shimla has the lowest atmospheric pressure, it will boil first.

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option (ii) Nsm^-2 

viscosity coefficient (η) = $\frac{Force}{Area*VelocityGradient}$

SI unit of (η)= Nsm^-2

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Option (iv) O₂, N₂, H₂, He

Higher the critical temperature of gases more easily, the gas will be liquefied. So, the order of liquefying of gases will be  O₂ > N₂ > H₂ >He. 

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Option (i) increases

Gay Lussac's law shows the direct relationship between the pressure and the temperature of a fixed amount of gas at constant volume.

Gay Lussac's law states that at constant volume, the pressure of a fixed amount of a gas is directly proportional to the temperature.

Therefore,  

P∝T   ……….at constant volume

Thus, pressure increases if the temperature is increased at a constant volume.

To elaborate more on this topic, we will see a real-life example.

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option (iii) 8 * 10⁴  Nm^-2 

Partial pressure of oxygen, Po₂= Xo₂   $*$ P_total

Mole fraction of O₂= $\frac{Moleofoxygen}{Molesofoxygen+Molesofhydrogen}$

= $\frac{4}{4+1}$ = $\frac{4}{5}$

Po₂= $\frac{4}{5}$ $*$ 1 = $\frac{4}{5}$  (?P_total = 1 atm)

1 atm =  1.1034 * 10⁵ Nm^-2 or Pa

Partial pressure of dioxygen = 0.8 *10⁵ = 8*10⁴  Nm^-2 

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option (iii) less than unit electronic charge 

Charge of 1 electron is 1.6 * 10 ^-19 C and the partial charge is always less than the unit electronic charge.

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option (iii) polarisability of interacting particles.

The energy of the London force or London dispersion force  is inversely proportional to (distance between two interacting particles)⁶ but their magnitude depends upon the polarisability of interacting particles.

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option  iii. p₁  < p₂ < p₃ < p₄

At a particular temperature, PV is constant

Therefore,   V ∝ $\frac{1}{\mathit{p}}$

So, as v₁ >  v₂  >  v₃  >  v₄   the order of pressure:  p₁  < p₂ < p₃ < p₄ .

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option (ii) surface tension 

Surface tension minimises the surface area of the liquid and at  minimum surface area, the liquid is in its the lowest energy state and hence most stable. Spherical shape of rain droplets has minimum surface area due to surface tension.