### use

Posted:

**Wed Jan 09, 2019 4:15 pm**when do you use this equation?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=123&t=39516

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Posted: **Wed Jan 09, 2019 4:15 pm**

when do you use this equation?

Posted: **Wed Jan 09, 2019 4:18 pm**

Which Equation?

Posted: **Wed Jan 09, 2019 4:20 pm**

Noh_Jasmine_1G wrote:when do you use this equation?

forgot to write the equation haha. its the partial pressure equation

Posted: **Wed Jan 09, 2019 4:26 pm**

If you mean P = (n/V)*R*T, you would use that in order to solve for concentration (n/V is the concentration) when given a pressure.

If you mean k = (P.products)/(P.reactants) you would use that to solve for the equilibrium constant or partial pressures, depending on your initial information.

If you mean k = (P.products)/(P.reactants) you would use that to solve for the equilibrium constant or partial pressures, depending on your initial information.

Posted: **Wed Jan 09, 2019 6:05 pm**

Dalton's partial pressure equation is Pt=Pa+Pb+... where Pt is total pressure of all gases in the reaction while Pa and Pb are individual gases- they can just be added up to find the total. You use it in many equilibrium scenarios where perhaps the total pressure is given so you have to solve for one of the individual gases' pressure and then find the equilibrium from there.

Posted: **Thu Jan 10, 2019 11:43 am**

Since we will be using the partial pressures of gasses to find the equilibrium constant of some reactions, we may be asked to calculate partial pressures from a total pressure. This only requires addition and subtraction because the partial pressures of gasses in a system will add up to the total pressure of the system.

Posted: **Thu Jan 10, 2019 12:10 pm**

The partial pressure equation is used to convert a gas from units of atm or bar to moles per liter. It is useful when we have a Kc value instead of Keq.

Posted: **Fri Jan 11, 2019 9:52 am**

In regards to the question above, when is Kp used?

Posted: **Fri Jan 11, 2019 10:08 am**

804788143 wrote:In regards to the question above, when is Kp used?

Kp is the same as Kc, but it just represents the equilibrium constant as a value of partial pressures rather than molar concentrations. You can use the equation mentioned in the responses above to convert between the two. You just must make sure that all of your values when solving for the equilibrium constant are the same, and sometimes must convert between partial pressure and molar concentration to do this.