chemistry : class11 Definition of Common Ion Effect : Common ion effect : Equilibrium MCQ Questions and Answers
Practice important
Definition of Common Ion Effect
MCQ questions and answers.
Page 1
of
1
|
10
MCQ Questions
1. What is the common ion effect?
A.
Increase in ionization of a weak electrolyte by adding a common ion
B.
Suppression of the ionization of a weak electrolyte by adding an electrolyte having a common ion
C.
Complete ionization of a strong electrolyte in water
D.
Formation of a precipitate when two gases are mixed
Correct Answer:
Suppression of the ionization of a weak electrolyte by adding an electrolyte having a common ion
Explanation:
The common ion effect is the suppression of the ionization of a weak electrolyte when a strong electrolyte containing one of its ions is added.
2. The common ion effect occurs when a weak electrolyte and a strong electrolyte have which type of ion in common?
A.
A common ion
B.
A common molecule
C.
A common neutron
D.
A common solvent only
Correct Answer:
A common ion
Explanation:
The effect is produced because both electrolytes provide the same ion in solution, called the common ion.
3. What happens to the ionization of acetic acid when sodium acetate is added to its solution?
A.
It increases greatly
B.
It remains completely unchanged
C.
It is suppressed
D.
It becomes complete
Correct Answer:
It is suppressed
Explanation:
Acetic acid and sodium acetate have the acetate ion in common. Adding sodium acetate therefore suppresses the ionization of acetic acid.
4. Which pair demonstrates the common ion effect?
A.
Hydrochloric acid and sodium chloride
B.
Acetic acid and sodium acetate
C.
Water and glucose
D.
Ethanol and methanol
Correct Answer:
Acetic acid and sodium acetate
Explanation:
Acetic acid is a weak electrolyte, and sodium acetate is a strong electrolyte containing the common acetate ion.
5. In the equilibrium CH3COOH ⇌ H+ + CH3COO−, which added substance provides a common ion?
A.
Sodium acetate
B.
Glucose
C.
Ethanol
D.
Pure water
Correct Answer:
Sodium acetate
Explanation:
Sodium acetate dissociates to provide CH3COO−, which is one of the ions already present in the acetic acid ionization equilibrium.
6. The common ion effect is mainly associated with the ionization of which type of electrolyte?
A.
Weak electrolyte
B.
Non-electrolyte only
C.
Metallic conductor only
D.
Solid element only
Correct Answer:
Weak electrolyte
Explanation:
The common ion effect is commonly described as the suppression of the ionization of a weak electrolyte by adding a strong electrolyte with a common ion.
7. When ammonium chloride is added to ammonium hydroxide solution, which ion causes the common ion effect?
A.
Chloride ion
B.
Ammonium ion
C.
Hydroxide ion
D.
Hydrogen ion
Correct Answer:
Ammonium ion
Explanation:
Ammonium hydroxide provides NH4+ and OH−, while ammonium chloride provides NH4+ and Cl−. Thus, NH4+ is the common ion.
8. What is the direct result of adding a common ion to a weak electrolyte solution?
A.
The weak electrolyte ionizes less
B.
The weak electrolyte ionizes completely
C.
The solvent changes into a solute
D.
The electrolyte disappears from the solution
Correct Answer:
The weak electrolyte ionizes less
Explanation:
Adding a common ion shifts the ionization equilibrium toward the unionized weak electrolyte, so its ionization decreases.
9. Which statement correctly defines the common ion effect?
A.
The increase in solubility caused by removing an ion
B.
The decrease in ionization caused by adding an electrolyte with an ion already present
C.
The conversion of a weak electrolyte into a strong electrolyte
D.
The reaction of an electrolyte with a metal
Correct Answer:
The decrease in ionization caused by adding an electrolyte with an ion already present
Explanation:
The common ion effect is the decrease in ionization of a weak electrolyte when another electrolyte supplies an ion already present in its equilibrium.
10. For the equilibrium NH4OH ⇌ NH4+ + OH−, which substance can produce the common ion effect?
A.
Ammonium chloride
B.
Sodium sulfate
C.
Potassium nitrate
D.
Glucose
Correct Answer:
Ammonium chloride
Explanation:
Ammonium chloride dissociates to produce NH4+, which is already present in the ionization equilibrium of ammonium hydroxide.
Short Questions and Answers
Practice short questions and answers related to
Definition of Common Ion Effect
.
Short questions are currently unavailable for this page.