volume change with inert gas

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ursulavictorino1K
Posts: 55
Joined: Sun Feb 17, 2019 12:15 am

volume change with inert gas

Postby ursulavictorino1K » Sun Jan 12, 2020 6:58 pm

Why doesn't the reaction shift when the pressure is changed by an inert gas?

Niharika 1H
Posts: 50
Joined: Thu Jul 25, 2019 12:16 am

Re: volume change with inert gas

Postby Niharika 1H » Sun Jan 12, 2020 7:01 pm

The reaction doesn't shift because although the pressure does increase, the partial pressures of the existing gasses aren't affected by adding an inert gas.

Gerald Bernal1I
Posts: 102
Joined: Thu Jul 11, 2019 12:16 am

Re: volume change with inert gas

Postby Gerald Bernal1I » Sun Jan 12, 2020 9:00 pm

The inert gas does not change the volume and therefore does not change the concentrations of the gases therefore it will not affect the equilibrium.

Sjeffrey_1C
Posts: 108
Joined: Wed Feb 20, 2019 12:17 am

Re: volume change with inert gas

Postby Sjeffrey_1C » Sun Jan 12, 2020 9:22 pm

In class, he explained that if the pressure of a reaction vessel is increased by adding inert gas, then moles of reactant, product and volume are constant, so there's no change in [R] and [P].

Connor Chappell 2B
Posts: 59
Joined: Wed Feb 20, 2019 12:16 am

Re: volume change with inert gas

Postby Connor Chappell 2B » Mon Jan 13, 2020 4:40 pm

The answer to your question is found in the equation PV=nRT, which can be rewritten as P=(nRT)/V. n/V is the mathematical notation for concentration, therefore P = (concentration)(RT). Thus, the reason that concentration of a substance does not change in a beaker when the pressure is increased by adding an inert gas. This is because we simply increase the number of moles (n) in the equation without changing V. Thus, when we take the ratio of the number of moles of the targeted substance (n), the Concentration will be the same because the ration of n/V has not changed.

JohannaPerezH2F
Posts: 94
Joined: Wed Sep 18, 2019 12:18 am

Re: volume change with inert gas

Postby JohannaPerezH2F » Mon Jan 13, 2020 4:58 pm

the reaction does not shift (concentration does not change) with an inert gas because in order to do so we would need volume to change.

EMurphy_2L
Posts: 128
Joined: Sat Sep 07, 2019 12:16 am

Re: volume change with inert gas

Postby EMurphy_2L » Mon Jan 13, 2020 5:02 pm

the only reason we think of the reaction shifting with increased pressure is presumably because we were taught it wrong before. While increasing pressure by like putting force on gas does shift the reaction, it's really because the volume is changing (not the pressure which is changing but not affecting the reaction). So if we add an inert gas the volume doesn't change so the reaction doesn't shift.
we just have to change our thinking of what actually affects a reaction (not pressure!)

Abigail_Hagen2G
Posts: 107
Joined: Fri Aug 09, 2019 12:17 am

Re: volume change with inert gas

Postby Abigail_Hagen2G » Tue Jan 14, 2020 2:18 pm

Okay, that makes more sense, thank you

cassidysong 1K
Posts: 100
Joined: Fri Aug 30, 2019 12:15 am

Re: volume change with inert gas

Postby cassidysong 1K » Tue Jan 14, 2020 9:57 pm

the inert gas doesn't change the physical characteristics of the products and reactants

Angela Prince 1J
Posts: 102
Joined: Sat Aug 24, 2019 12:17 am

Re: volume change with inert gas

Postby Angela Prince 1J » Wed Jan 15, 2020 4:30 pm

the inert gas will not affect the concentration or partial pressures of the products or the reactants, they will remain constant so the reaction does not shift.


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