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Phosphorus pentachloride dissociates as follows, in a closed reaction vessel,
PCl₅ (g) ⇌ PCl₃(g) + cl₂(g)
If total pressure at equilibrium of the reaction mixture is P and degree of dissociation of PCl₅ is x, the partial pressure of PCl₃ will be

$open parentheses fraction numerator straight x over denominator straight x plus 1 end fraction close parentheses straight P$
$open parentheses fraction numerator 2 straight x over denominator straight x plus 1 end fraction close parentheses straight P$
$open parentheses fraction numerator straight x over denominator straight x minus 1 end fraction close parentheses straight P$
$open parentheses fraction numerator straight x over denominator straight x minus 1 end fraction close parentheses straight P$

556 Views

12.

The formation of the oxide ion O^2-(g) requires first an exothermic and then an endothermic step as shown below
$straight O space left parenthesis straight g right parenthesis space space plus straight e to the power of minus space straight O to the power of minus left parenthesis straight g right parenthesis space increment straight H to the power of straight o space equals space minus space 142 space kJ space mol to the power of negative 1 end exponent straight O to the power of minus space left parenthesis straight g right parenthesis space space plus straight e to the power of minus straight O to the power of 2 minus end exponent space left parenthesis straight g right parenthesis increment straight H to the power of straight o space equals space 844 space kJ space mol to the power of minus space$

Oxygen is more electronegative
O^- ion has comparatively larger size than oxygen atom
O^- ion will tend to resist the addition of another electron
O^- ion will tend to resist the addition of another electron

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13.

As the temperature is raised from 20°C to 40°C, the average kinetic energy of neon atoms changes by a factor of which of the following?

1/2
2
313/293
313/293

163 Views

14.
In Vander Waals equation of state of the gas law, the constant ‘b’ is a measure of

intermolecular repulsions

intermolecular collisions per unit volume

Volume occupied by the molecules

Volume occupied by the molecules

Volume occupied by the molecules

Vander Waals' equation for one mole of a gas is

where, b is the volume correction i.e., the volume occupied by the molecules.

166 Views

15.

An ideal gas expands in volume from 1×10^-3 m³ to 1×10^-2 m³ at 300 K against a constant pressure of 1×10⁵ Nm^-2. The work done is

-900 J
900 J
2780 J
2780 J

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16.

For same mass of two different ideal gases of molecular weights M₁ and M₂, Plots of log V vs log p at a given constant temperature are shown. Identify the correct option.

M₁ > M₂
M₁ = M₂
M₁ < M₂
Can be predicted only if temeperature is known

17.

Which of the following has the dimension if [ML⁰T^-2]?

Coefficient of viscosity
Surface tension
Vapour pressure
Kinetic energy

18.

The boiling points of HF, HCl, HBr and HI follow the order

HF> HCl > HBr > HI
HF> HI> HBr > HCl
HI> HBr > HCl> H
HCl > HF> HBr > HI

19.

At a certain temperature, the value of the slope of the plot of osmotic pressure ( $π$ ) against concentration (C in molL^-1) of a certain polymer solution is 291R. The temperature at which osmotic pressure is measured, is (R is gas constant)

271°C
18°C
564 K
18 K

20.

For one mole of an ideal gas, the slope of V vs. T curve at constant pressure of 2 atm is X L mol^-1 K^-1.The value of the ideal universal gas constant 'R' in terms of X is