## Homework 11.41

Danah Albaaj 1I
Posts: 50
Joined: Fri Sep 29, 2017 7:07 am

### Homework 11.41

I'm not entirely sure how to approach this problem. It states a 25.0-g sample of ammonium carbamate, NH4(NH2CO2), was placed in an evacuated 0.250-L flask and kept at 25 C. At equilibrium, 17.4 mg of CO2 was present. What is the value of Kc for the decomposition of ammonium carbamate into ammonia and carbon dioxide? The reaction is NH4(NH2CO2)(s) Δ 2 NH3(g) + CO2(g). I've tried 6 different approaches and received results close to the answer, but if someone could explain what exactly I am supposed to do I would greatly appreciate it.

EveEmm3D
Posts: 28
Joined: Fri Sep 29, 2017 7:07 am

### Re: Homework 11.41

The equilibrium constant is equal to Kc = [NH3]^2[CO2]. The concentration of ammonium carbamate doesn't go into the equation because it is in solid form. You can calculate the concentration of CO2 by first finding the number of mol of CO2 and dividing by the volume of the flask. As for NH3, the balanced chemical equation tells us that there twice as many mol of NH3 as there are mol of CO2, so we can calculate the concentration of NH3 as well. Hope this helps!