total pressure

[705596384]

How do we solve for total pressure at equilibrium when given the equilibrium constant? In question 4 from the achieve homework, the equilibrium constant Kp was 351 and the initial pressure was 0.0340 bar, PCl3(g)+Cl2(g)↽−−⇀PCl5(g). Do we always have give the equilibrium pressure in bar units?

[IA_1D]

Hi, you set up the equation by making a table for initial and equilibrium pressures (ICE box). Through there you try to find the equation for kp, which i think for you would be 351=(0.340-x)/(x^2). You solve for x, and then add all the partial pressures together to get the total pressure. The partial pressures would be the sum of the sum of pressures of the reactants and products.

Hope this helps!

[Gabriel McDonald 1J]

The total pressure is just the sum of all the partial pressures (i.e. the sum of the pressures of the reactants and products). You'd need to set up an ICE box, and solve for the pressures of each species at equilibrium. Then, add them all up!

[Jonathan Sautter 1J]

In order to solve this question, you need to set up an ICE table and have product PCl5 be .034-x and have the two reactants each be +X. Once this ICE table is complete, set [products]/[reactants] (or [.034-x]/[x^2] equal to 351 and solve the quadratic to get x. Once x is found, plug it back into the equations to get the equilibrium pressure of each molecule and add them up to get the total equilibrium pressure. Yes, typically equilibrium pressure will be in bars.

[Savannah Licciardello 2C]

For the units, they typically will be in bar but if they are in atm or something like that its the same concept. Just use whatever units the question asks for.

[Ashley Presnell 1C]

If given the partial partial pressure of the reactant and Kp, we can use an ICE box to solve for the partial pressures of the products and reactants at equilibrium the same way we solve for equilibrium concentrations using Kc. Once we know all the partial pressures at equilibrium, we solve for the total pressure at equilibrium by calculating the sum of the partial pressures of the reactants and products at equilibrium that we calculated through the ICE box calculations.

[Ashrita Singh 2F]

For units, I think you can use either atm or bars, but for this problem bars is preferred.

[emily3L]

The total pressure is the sum of all the partial pressures, and you can use an ICE box.

[trevina_brown_2A]

Using an ICE box will help you and then you will be able to solve for the pressures of each species at equilibrium.