Why doesn't the amount of Cl increase?

AI Thread Summary
The discussion centers on why the amount of chlorine does not increase when an inert gas is introduced into a reaction at equilibrium. Participants explain that while the total pressure increases, the partial pressures of the reacting gases remain constant, which means the equilibrium position is unaffected. The reaction's equilibrium constant (K) is only influenced by temperature, not by the addition of inert gases. Thus, even though the reaction may proceed forward, the concentrations of products and reactants do not change. The conclusion is that introducing an inert gas does not alter the equilibrium state of the reaction.
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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