:idiot2:

**Adding inert gased increases the pressure of all species in a reaction.**

However, i wonder why it does not affect the position of the equilibrium system?.

Can anyone explain to me please'''

The part in bold is incorrect. It increases the total pressure of the system, but it does not affect any other species' partial pressure (1). Hence, it does not affect the other species' concentration (2), and consequently, the system's reaction quotient.

Explaining (1):

Consider the system with gas

and

.

Now, insert inert gas

Now,

Hwoever, the individual partial pressures,

and

have not changed.

Explaining (2):

Using the ideal gas equation:

Since

and

are constant for any given temperature, then if

does not change (as explained above), therefore

does not change.

Hence, if the system is at equilibrium

(reaction quotient) does not change, and so it remains that:

. The system stays in equilibrium.