## Example 5I.4

Paige Lee 1A
Posts: 136
Joined: Sat Sep 07, 2019 12:16 am

### Example 5I.4

For this example, how do you know to find the partial pressures and not the concentrations at equilibrium?

Zaynab Hashm 2I
Posts: 110
Joined: Wed Sep 11, 2019 12:15 am
Been upvoted: 1 time

### Re: Example 5I.4

If you mean why we have to use partial pressure, it's because the question mentions that they're in a gas-phase equilibrium. We use partial pressure for gases.

Alex Tchekanov Dis 2k
Posts: 118
Joined: Sat Aug 24, 2019 12:16 am

### Re: Example 5I.4

If you want to convert from concentration to partial pressure you have to use the ideal gas law: PV=nRT
P=(n/V)RT
P=ConcRT
Cont=P/RT

Pegah Nasseri 1K
Posts: 100
Joined: Wed Feb 27, 2019 12:15 am

### Re: Example 5I.4

Always when calculating K for gases, partial pressure is used. However, if the question specifically asks you to find $K_{c}$ then you would use the concentration of the gases. You would convert the partial pressure of the gases to molar concentration using the equation PV=nRT (n/V (concentration) = P/RT).

705302428
Posts: 50
Joined: Sat Aug 24, 2019 12:16 am

### Re: Example 5I.4

Because we use partial pressure when dealing with gasses.