## Table 5G.2

Amy Luu 2G
Posts: 105
Joined: Wed Sep 18, 2019 12:19 am

### Table 5G.2

In the table, it gives us both the k and kc values for the reactions. What is the difference between the two and how do we know which one to use? For example in problem 5I.13 how do we know whether to use K or Kc when finding the reaction composition?

Sahil Jog 1F
Posts: 126
Joined: Thu Jul 11, 2019 12:16 am

### Re: Table 5G.2

Typically, you would use Kc when you are given the concentration of the compounds, while Kp when you are working with gases. But in this case, it would not really matter which ones you use to calculate, since the equilibrium ratio would be the same.

Nuoya Jiang
Posts: 99
Joined: Sat Sep 14, 2019 12:17 am

### Re: Table 5G.2

We can use the Kc in this table if the question asks us to solve for concentrations of gases in the reaction, such as question 5.39.

Rory Simpson 2F
Posts: 106
Joined: Fri Aug 09, 2019 12:17 am

### Re: Table 5G.2

In the table I think that K is just referring to Kp based on the fact that all of the equations only have gases. So, use "K" in the table if you are solving using partial pressure and use "Kc" in the table if using concentrations.

EllieSchmidtke_4I
Posts: 51
Joined: Wed Feb 20, 2019 12:16 am

### Re: Table 5G.2

For problem 5I.3, why would you use Kc = 160 from Table 5G.2 instead of Kc = 794 or Kc = 54?

JChen_2I
Posts: 107
Joined: Fri Aug 09, 2019 12:17 am

### Re: Table 5G.2

EllieSchmidtke_4I wrote:For problem 5I.3, why would you use Kc = 160 from Table 5G.2 instead of Kc = 794 or Kc = 54?

The problem tells you the equilibrium mixture is at 500K which is why you use Kc=160