Chapter Exam

Chapter 6: Equilibrium — Online MCQ Test

Q: Which of the following is an example of physical equilibrium?

Answer: C. H2O(l) ⇌ H2O(g) in a closed container — Physical equilibrium involves phase changes, such as liquid-vapour equilibrium in a closed container.

Q: For the equilibrium H2(g) + I2(g) ⇌ 2HI(g), if the concentration of HI is increased, the equilibrium will shift:

Answer: B. To the left — Adding product makes the system shift in the reverse direction to consume the excess HI.

Q: For the reaction PCl5(g) ⇌ PCl3(g) + Cl2(g), which action will shift equilibrium to the right?

Answer: C. Removing PCl3 — Removing a product causes the equilibrium to shift right to produce more products.

CHEMISTRY · CLASS 11 INTER I YEAR · Andhra State Board

Practice Chapter 6: Equilibrium with a free chapter-wise online MCQ test for Andhra State Board CLASS 11 INTER I YEAR CHEMISTRY. This chapter covers: Chemical equilibrium Physical equilibrium Equilibrium constant Le Chateliers principle Ionic equilibrium pH Buffer solution Acid Base Solubility product. AI-generated questions from basic to board-exam level, with instant results and explanations.

Questions

20m

Time Limit

Attempts Left

10 random questions from this chapter (mixed difficulty)
Questions you've seen before won't repeat until the pool resets
You have 20 minutes — exam auto-submits when time is up
Maximum 3 attempts per chapter
Results and explanations shown immediately after submission

New here? Register free — includes 3 free chapter exams.

Chapter 6: Equilibrium — Important Questions & Answers (FAQ)

Frequently asked questions from Andhra State Board CLASS 11 INTER I YEAR CHEMISTRY — Chapter 6: Equilibrium, with answers and explanations. These are sample questions; the exam has its own separate question set.

What is meant by chemical equilibrium?

A. A state in which reactants are completely consumed
B. A state in which the rates of forward and backward reactions are equal ✓
C. A state in which only the forward reaction occurs
D. A state in which the reaction stops permanently

Answer: B. A state in which the rates of forward and backward reactions are equal
In chemical equilibrium, both forward and backward reactions continue, but their rates become equal, so the concentrations remain constant.

Which of the following is an example of physical equilibrium?

A. N2 + 3H2 ⇌ 2NH3
B. CaCO3(s) ⇌ CaO(s) + CO2(g)
C. H2O(l) ⇌ H2O(g) in a closed container ✓
D. HCl(aq) + NaOH(aq) → NaCl(aq) + H2O(l)

Answer: C. H2O(l) ⇌ H2O(g) in a closed container
Physical equilibrium involves phase changes, such as liquid-vapour equilibrium in a closed container.

For the equilibrium H2(g) + I2(g) ⇌ 2HI(g), if the concentration of HI is increased, the equilibrium will shift:

A. To the right
B. To the left ✓
C. No shift
D. Cannot be predicted

Answer: B. To the left
Adding product makes the system shift in the reverse direction to consume the excess HI.

For the reaction PCl5(g) ⇌ PCl3(g) + Cl2(g), which action will shift equilibrium to the right?

A. Adding Cl2
B. Increasing pressure
C. Removing PCl3 ✓
D. Decreasing temperature if the forward reaction is endothermic

Answer: C. Removing PCl3
Removing a product causes the equilibrium to shift right to produce more products.

Which of the following is the most appropriate explanation for why HCl is not used to make a buffer with CH3COOH?

A. HCl is a weak acid
B. HCl is a strong acid and has no conjugate base to provide buffering action ✓
C. HCl reacts only with bases, not acids
D. HCl increases pH too much

Answer: B. HCl is a strong acid and has no conjugate base to provide buffering action
A buffer requires a weak acid and its conjugate base or a weak base and its conjugate acid; HCl does not provide a weak conjugate pair.