# Keg with pressure

#### sciencegod

##### Super Member
10+ Year Member
if it moves to the rigjt with pressuere why does the keq not change

#### TRN1983

##### MS1 - I.e. "Know nothing"
10+ Year Member
Things don't necessarily move to the right with pressure. Remember that pressure of a gas is directly dependent on the number of moles of a gas that are present. So, if you have the following:

3X <--> Y and you increase pressure then Le Chatlier's principle will try to conteract the increase in pressure by decreasing the number of moles in the gas (creating more Y).

So, for the above equilibrium pressure increases shift to the right and pressure decreases shift to the left in order to satisfy Le Chatlier's principle.

#### sciencegod

##### Super Member
10+ Year Member

anyways, if it moves to the right why doesn't the keg also get bigger.

#### sciencegod

##### Super Member
10+ Year Member
doesnt any one know rhe ansew to this question
it doesn't seem like it should be such a hard questin. seems pretty basic

#### chessxwizard

##### Full Member
10+ Year Member
7+ Year Member
Because keq doesn't change with pressure, only temperature.

#### sciencegod

##### Super Member
10+ Year Member
i know it doesn't my question is why.

#### Sublimation

##### Full Member
10+ Year Member
5+ Year Member
if it moves to the rigjt with pressuere why does the keq not change

Hope this helps. Now remember that when dealing with gases, the Q is calculated using the partial pressures. Therefore ur not dealing with concentrations, so unless you physically add more reagent or product or any of the species that u have, the partial pressure wont change. Subsequently if there is no change in Q then there is no effect on the equilibrium position. Hope it helps remember we are not dealing with moles perliter crap here we are dealing with partial pressure when it comes to gases.

#### zuma35

##### Full Member
10+ Year Member
5+ Year Member
Hope this helps. Now remember that when dealing with gases, the Q is calculated using the partial pressures. Therefore ur not dealing with concentrations, so unless you physically add more reagent or product or any of the species that u have, the partial pressure wont change. Subsequently if there is no change in Q then there is no effect on the equilibrium position. Hope it helps remember we are not dealing with moles perliter crap here we are dealing with partial pressure when it comes to gases.

Actually, adding or removing reactants or products will also have no effect on the equilibrium constant. Only a change of temp would change K.

#### Sublimation

##### Full Member
10+ Year Member
5+ Year Member
Actually, adding or removing reactants or products will also have no effect on the equilibrium constant. Only a change of temp would change K.

My bad, i meant to say it drives the reaction in a certain direction. my bad guys i was taking a rbeak from studying so i wasnt very accurate. The part in regards to the partial pressures is right. Equilibirium is a function of rate and rate is a function fo temprature, therefore it Keq will only change if temp changes and nothing else. The definition of chemical equilibrium is a description of concentrations of the products and reactants when the NET rate is Zero. Thereofre temp is the only thing that can change keq b definition. lol i prolly messed up here too guys but someon double check that and let me kno its late here on the east coast and my brain is fried.

#### zuma35

##### Full Member
10+ Year Member
5+ Year Member
Here's another way to say it. If you have 4 moles on the left and 2 on the right, and you increase the pressure, you are affecting more moles on the left than on the right. Therefore the partial pressures on the left have increased relative to the right side, and the K eq would actually be temporarily reduced. Therefore, the reaction moves to the right to restore the original K eq.

This thread is more than 12 years old.

Your message may be considered spam for the following reasons:

4. It is very likely that it does not need any further discussion and thus bumping it serves no purpose.
5. Your message is mostly quotes or spoilers.