Textbook Problem 5I.13

[Shreya Lakkaraju 2E]

Hi! Can someone please explain how to go about solving textbook problem 5I #13? I am not getting the answers listed in the answer key. Thank you!

[Nhi Pham 3D]

For this question, we are given the concentration of HI and I2 and the equilibrium constant at 500 K (160 -> from Table 5G.2). We can find the concentration of H2 by writing out the equation for K using the balanced equation (H2 + I2 <=> 2 HI).

Using the balanced equation, the equation for the equilibrium constant is K = [HI]^2 / ([H2][I2]). Plug in the values you're given (K, [HI], and [I2]) and you should be able to solve for [H2]. Hope this helps!

[Nathalia Garibay 1D]

Hi! Can someone please explain how to go about solving textbook problem 5I #13? I am not getting the answers listed in the answer key. Thank you!

The first thing you have to do is convert the units. Since we are given mmol, you have to divide the value by 1000 to get mol units. Next thing is to divide mol units by the number of liters. We have a 2L solution in this case. Your final value is in units of mol/L which are the units needed to set up your ice table.

From there you should be able to solve for your ICE table and plug in your Kc value from the table to solve for x.

Hope this helps!

[Abeni Liu 2B]

Hi, just a quick follow up question for this problem. The F2 concentration is listed as 8 x 10^-4 for part b. Why is there only one sigfig? I got 8.4 x 10^-4. Thank you!

[Sally_Luo_3F]

Hi, just a quick follow up question for this problem. The F2 concentration is listed as 8 x 10^-4 for part b. Why is there only one sigfig? I got 8.4 x 10^-4. Thank you!

I think it might be because it was just during the process of the calculation so they didn't follow the sigfig, but at the end they used 2 sigfig.