In aqueous solution the ionization constants for carbonic acid are
K₁ = 4.2 x 10^–7 and K₂ = 4.8 x 10^–11
Select the correct statement for a saturated 0.034 M solution of the carbonic acid.

The equilibrium constants K_P1 and K_P2 for the reactions X $$\leftrightharpoons$$ 2Y and Z $$\leftrightharpoons$$ P + Q, respectively are in the ratio of 1 : 9. If the degree of dissociation of X and Z be equal then the ratio of total pressure at these equilibria is :

For the following three reactions a, b and c, equilibrium constants are given:
a. CO (g) + H₂O (g) $$\leftrightharpoons$$ CO₂(g) + H₂ (g) ; K₁
b. CH₄ (g) + H₂O (g) $$\leftrightharpoons$$ CO(g) + 3H₂ (g) ; K₂
c. CH₄ (g) + 2H₂O (g) $$\leftrightharpoons$$ CO₂(g) + 4H₂ (g) ; K₃

Phosphorus pentachloride dissociates as follows, in a closed reaction vessel
PCl₅ (g) $$\leftrightharpoons$$ PCl₃ (g) + Cl₂ (g)
If total pressure at equilibrium of the reaction mixture is P and degree of dissociation of PCl₅ is x, the partial pressure of PCl₃ will be