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QJEEM23Chaf9d: JEE Main 2023 Chemistry - Class 11 JEEM23Chaf9d Solution: The effect of addition of helium gas to the following reaction…

The effect of addition of helium gas to the following reaction in equilibrium state, is :

PCl5(g)⇌PCl3(g)+Cl2(g)\mathrm{PCl}_{5}(\mathrm{g}) \rightleftharpoons \mathrm{PCl}_{3}(\mathrm{g})+\mathrm{Cl}_{2}(\mathrm{g})

Multiple Choice Options

  • A the equilibrium will shift in the forward direction and more of Cl2\mathrm{Cl}_{2} and PCl3\mathrm{PCl}_{3} gases will be produced.
  • B addition of helium will not affect the equilibrium.
  • C helium will deactivate PCl5\mathrm{PCl}_{5} and reaction will stop.
  • D the equilibrium will go backward due to suppression of dissociation of PCl5\mathrm{PCl}_{5} .

Step-by-Step Verified Solution

PCI5( g)⇌PCl3( g)+Cl2( g)\mathrm{PCI}_5(\mathrm{~g}) \rightleftharpoons \mathrm{PCl}_3(\mathrm{~g})+\mathrm{Cl}_2(\mathrm{~g})

Case 1 : At constant pressure, the addition of inert gas (helium) will shift the reaction where number of moles of gaseous substances are more hence, the reaction will proceed in forward direction. Then answer will be AA .

Case 2 : At constant volume, addition of He will not affect the equilibrium so reaction will not shift in any direction then answer will be BB .

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