## 5I. 19

Janet Nguy 2C
Posts: 115
Joined: Sat Aug 24, 2019 12:17 am

### 5I. 19

Hello! for question 5I19, how do you go about incorporating the "60% of H2 reacted at equilibrium" in the calculations for K?

Here is the full problem:

5I.19 A reaction mixture that consisted of 0.400 mol H2 and 1.60
mol I2 was introduced into a flask of volume 3.00 L and heated. At
equilibrium, 60.0% of the hydrogen gas had reacted. What is the
equilibrium constant K for the reaction H2(g) + I2(g) ->
2 HI(g) at this temperature?

(-> is an equilibrium symbol)

Shivam Rana 1D
Posts: 106
Joined: Fri Aug 09, 2019 12:16 am

### Re: 5I. 19

If you know 60% reacted then you know the moles that were used and you can use that to find the leftover moles for the other reactant and the moles of product made. You can use these new concentrations to find the equilibrium constant.

Jessica Chen 2C
Posts: 103
Joined: Thu Jul 11, 2019 12:17 am

### Re: 5I. 19

Since you know 60% of H2 reacted, you know 40% is remaining at equilibrium. Thus, you can find the equilibrium value of H2 by multiplying the initial value of H2 by 0.4.

Megan Vu 1J
Posts: 101
Joined: Thu Jul 25, 2019 12:15 am

### Re: 5I. 19

For this specific problem, you know that 60% must be left as the equilibrium. Thus, when you are calculating the equilibrium, all you have to do to find x is getting 0.133 - x = .4(0.133). 40% of the actual product must be left for H2.
Then, you are able to find the x and you can plug it in to find the equilibrium concentrations of H2, I2, and HI to figure out the K.