Chemistry - Chemical Equilibrium Question with Solution | TestHub
Match Column I with Column II for the reaction: 3A(g) ⇌ 2B(g) + C(s); Δ H = -ve
Column I | Column II |
|---|---|
P) Increase in total pressure at equilibrium | i) Increase in moles of A |
Q) Increase in volume at equilibrium | ii) Increase in moles of B |
R) Addition of He(g) at constant pressure | iii) Increase in moles of C |
S) Decrease in temperature at constant volume | iv) Increase in molar concentration of A |
| v) Increase in molar concentration of B |
Options:
Answer:
Solution:
For the reaction, Δng = 2 - 3 = -1, and the forward reaction is exothermic.
P: Raising the total pressure by compression shifts the equilibrium forward. Consequently, the moles of B increase (ii) and the moles of C increase (iii). Compression increases every gas concentration, and the partial forward shift only reduces this rise, so [A] increases (iv) and [B] also increases (v).
Q: Increasing the volume shifts the equilibrium backward. Therefore, the moles of A increase (i), while all gas concentrations fall.
R: Adding He at constant pressure enlarges the volume, which again results in a backward shift, leading to (i).
S: Since the reaction is exothermic, lowering the temperature shifts it forward. This causes the moles of B to increase (ii), the moles of C to increase (iii), and with a fixed volume, [B] increases (v), while the moles and concentration of A decrease.
The correct mapping is option (b).
