[Epiclightning]

Ammonium Carbamate dissociates as NH₂COONH₄ = 2NH₃ + CO₂.
In a closed vessel containing ammonium carbamate in equilibrium, ammonia is added such that the partial pressure of ammonia now equals the original total pressure. Calculate the ratio of partial pressure of CO₂ now to the original partial pressure of CO₂.

No actual values of the partial pressures are given, and I don't think the partial pressure ratio is proportional to the molar ratio, so how can I formulate an equation that I can actually solve? Nothing seems to be working out.

[Borek]

Just a reminder: please don't give final answers.

Assume original partial pressure of CO₂ was p.

If the carbamate was the only source of gases - what was the partial pressure of ammonia (expressed using p)?

What was the total pressure? What was Kp (all expressed using p)?

Now, after the ammonia was added, p' is the new pressure of ammonia. Can you express it using p? Can you use everything found earlier to express new pressure of CO₂ using p?

[Epiclightning]

Well, P_Carbamate + P_NH3 + p = P_Total at equilibrium, but how can I express ammonia's pressure using only p?

[Borek]

Carbamate itself is not volatile, it is present only as the solid.

Think about stoichiometry.