Why doesn't the amount of Cl increase?

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Discussion Overview

The discussion revolves around the effects of introducing an inert gas into a chemical reaction at equilibrium, specifically questioning why the amount of chlorine formed does not increase despite the reaction proceeding in the forward direction. The scope includes theoretical considerations of chemical equilibrium and the implications of changing pressure and volume.

Discussion Character

  • Debate/contested
  • Technical explanation
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that introducing an inert gas will cause the reaction to proceed forward, implying an increase in chlorine production.
  • Another participant argues that the introduction of an inert gas increases the partial pressures of the components, which may favor the reverse reaction instead.
  • A different participant questions the initial claim, asking for clarification and suggesting the use of the formula for Kp to explain the reasoning.
  • One participant presents a mathematical approach, stating that increasing total pressure while keeping volume constant will affect the mole fractions of the gases, potentially leading to more reactants being produced.
  • Another participant reiterates the mathematical reasoning, emphasizing that while total pressure increases, the partial pressures of the reacting components remain constant, suggesting no effect on equilibrium.
  • A later reply acknowledges a mistake, indicating a recognition of the complexity of the discussion.

Areas of Agreement / Disagreement

Participants express differing views on the effects of introducing an inert gas, with no consensus reached on whether it favors the forward or reverse reaction. The discussion remains unresolved regarding the implications for the amount of chlorine formed.

Contextual Notes

Participants reference the equilibrium constant K and its dependence on temperature, but there are unresolved assumptions regarding the conditions of the system and the definitions of terms used in the discussion.

navneet9431
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Homework Statement


fa1f639387c513387662f7fb67cc778e3728c620.jpg


Homework Equations



Formula of Kp and Kc

The Attempt at a Solution


You will easily be able to identify that the reaction will proceed in the forward direction when some inert gas is introduced.
So,my question is that why won't the amount of chlorine formed increase in that process(because the reaction is proceeding forward)?

I will be thankful for any help!
 

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To my knowledge, if you insert some inert gas the partial pressure of the components increases and so the inverse reaction in favored. Intuitively think about it: you have two separate molecules, if you try to push them together then it will be reasonable that they will react.
 
navneet9431 said:
You will easily be able to identify that the reaction will proceed in the forward direction when some inert gas is introduced.
The gases are at equilibrium.
Sorry, but I cannot identify that the reaction will proceed in the forward direction when an inert gas is introduced.
Perhaps you could explain your reasoning, through the use of the formula of Kp
 
I think the following. I don't know if it is rigorous enough for you.

Consider the gas-phase reaction ##A → B + C## $$K = \frac {P x_B P x_C} {P x_A} = P \frac {x_B x_C} {x_A}$$ if ##P## increases then ##\frac {x_B x_C} {x_A}## must decrease to keep ##K## constant (remember that ##K## is a function of the Temperature only). Introducing an inert gas obviously increase the pressure if you keep the volume constant.

So more ##A## is produced
 
dRic2 said:
I think the following. I don't know if it is rigorous enough for you.

Consider the gas-phase reaction ##A → B + C## $$K = \frac {P x_B P x_C} {P x_A} = P \frac {x_B x_C} {x_A}$$ if ##P## increases then ##\frac {x_B x_C} {x_A}## must decrease to keep ##K## constant (remember that ##K## is a function of the Temperature only). Introducing an inert gas obviously increase the pressure if you keep the volume constant.

So more ##A## is produced
But if you introduce an inert gas, the mole fractions of the individual gasses will also decrease.
 
When an inert gas is added to the system in equilibrium at constant volume V, the total pressure will increase, but the partial pressures pi of the reacting components remain constant:

pi = ni RT / V with ni the moles of gas component i

Hence, there will be no effect on the equilibrium.
 
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My mistake, I'm sorry.
 

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