Answer:
0.27 atm
Explanation:
At 25ºC, Kp = 2.9 x 10⁻³ for the reaction NH₄OCONH₂(s) ⇌ 2 NH₃(g) + CO₂(g). In an experiment carried out at 25ºC, a certain amount of NH₄OCONH₂ is placed in an evacuated rigid container and allowed to come to equilibrium. Calculate the total pressure in the container at equilibrium.
Step 1: Make an ICE chart
Solid and liquids are ignored in ICE charts.
NH₄OCONH₂(s) ⇌ 2 NH₃(g) + CO₂(g)
I 0 0
C +2x +x
E 2x x
Step 2: Write the pressure equilibrium constant expression (Kp)
Kp = [NH₃]² × [CO₂]
Kp = (2x)² × x
2.9 × 10⁻³ = 4 x³
x = 0.090 atm
Step 3: Calculate the pressures at equilbrium
pNH₃ = 2x = 2(0.090 atm) = 0.18 atm
pCO₂ = x = 0.090 atm
The total pressure is:
P = 0.18 atm + 0.090 atm = 0.27 atm
