Chemistry - Chemical Equilibrium Question with Solution | TestHub
For an endothermic reaction: 2A(g) + B(g) ⇌ 2C(g)
Match Column I with Column II (curves I, II, III show the concentrations of A, B and C against time; the change is applied at the marked instant)
Column I | Column II |
|---|---|
P)
| i) Increase in temperature |
Q)
| ii) Increase in pressure |
R)
| iii) Addition of C at equilibrium |
S)
| iv) Addition of inert gas at constant pressure |
| v) Increase in volume |
Options:
Answer:
Solution:
The reaction is endothermic with Δng = 2 - 3 = -1.
Graph P: All concentrations suddenly increase, then reactants decrease and the product increases. This indicates compression due to an increase in pressure, P-ii.
Graph Q: The product concentration suddenly increases while the reactant concentrations rise gradually. This indicates the addition of product C at equilibrium, Q-iii.
Graph R: There is no sudden change in concentrations; the reactants gradually decrease, and the product increases, indicating a forward shift. For an endothermic reaction, this is caused by an increase in temperature, R-i.
Graph S: All concentrations suddenly decrease, then the reactants increase, and the product decreases. This indicates dilution by adding an inert gas at constant pressure or by an increase in volume, S-iv and S-v.
The correct mapping is option (d).
