Tag: electrochemistry

Questions Related to electrochemistry

An electrolytic cell was set up. Water is placed in the cell and battery is switched on. The bulb is also connected through a battery. The bulb will:

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. glow.

  2. not glow.

  3. depends on the amount of water.

  4. None of the above.

Show answer
Correct Option: A
Explanation:

Water has some impurities in it. So the impurities will carry the current and the bulb will glow.

An electrolytic cell was set up. Ammonium hydroxide is placed in the cell and battery is switched on. The bulb is also connected through a battery. The bulb will:

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. glow brightly

  2. glow dimly

  3. not glow

  4. depends on the amount of ammonium hydroxide

Show answer
Correct Option: B
Explanation:

Ammonium hydroxide is a weak base so it has less ions to carry the current. So the circuit will be completed and the bulb will glow dimly.

The electrical conductivity of a solution depends upon :

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. its dilution

  2. its pressure

  3. the number of ions

  4. its temperature

Show answer
Correct Option: C

Which of the following is not a property of metallic conduction?

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. The flow of electricity takes place by flow of electrons

  2. There is no decomposition of the parent metal

  3. Metals are good conductors of electricity in solid state and in the molten state

  4. None of the above

Show answer
Correct Option: D
Explanation:
The properties of metallic conduction are:
1. The flow of electricity takes place by a flow of electrons.
2. There is no decomposition of the parent metal
3. Metals are good conductors of electricity in solid state and in the molten state

Conduction of electricity takes place due to the presence of :

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. free atoms

  2. free ions

  3. molecules

  4. gas dissolved in water

Show answer
Correct Option: B
Explanation:

Conduction of electricity takes place due to the presence of free ions.

Which of the following sentences is/are true?

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. Electrolytic conduction involves chemical changes

  2. Metallic conduction does not involve chemical changes

  3. Both of the above

  4. None of the above

Show answer
Correct Option: C
Explanation:

Electrolytic conduction occurs when a voltage is applied across the electrodes dipped in the electrolytic solution. The ions present in the electrolyte moves. The cations move towards the cathode. In the cathode the cations undergo reduction. The anions move towards the anode. In the anode the anions undergo oxidation. Thus electrolytic conduction accompanies a chemical change.
But no such chemical change occurs in case of metallic conduction.

Assertion: A 0.2M solution of carbonic acid is a weaker conductor of electricity than a 0.2M solution of $HBr$.

Reason: In solutions with the same concentration of solute molecules, $H _2CO _3$ is less dissociated than $HBr$.

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. The Assertion and Reason are correct and Reason is the correct explanation of Assertion

  2. Both the Assertion and Reason are correct and Reason is NOT the correct explanation of Assertion

  3. The Assertion is correct but Reason is not correct

  4. The Assertion is not correct but Reason is correct

  5. Both the Assertion and Reason are not correct

Show answer
Correct Option: A
Explanation:

Option A is the correct answer.

$ {HBr} $ dissociates completely in a solution forming $ {H}^{+} $ and $ {Br}^{-} $ ions. Whereas, $ {H} _{2}{C}{O} _{3} $ partially dissociates in a solution forming $ {H}^{+} $ and $ {HCO} _{3}^{-} $ ions. Thus in the same concentration of both the acids $ {HBr} $  is a stronger acid than $ {H} _{2}{C}{O} _{3} $. 
As $ {HBr} $  dissociates completely,  $ {H}^{+} $ ion concentration is more in this case, and hence $ {HBr} $ is a good conductor of electricity.

Which of the following sentences about conduction is/are true?

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. Electrolytic conduction involves transfer of matter

  2. Metallic conduction does not involve transfer of matter

  3. Both of the above

  4. None of the above

Show answer
Correct Option: C
Explanation:

In electrolytic conduction, a voltage is applied across the electrodes dipped into the electrolytic solution. There are ions present in electrolytic solution. Because of the voltage applied, electric current will flow in the solution. The ions will move in the solution. The cations will move towards the cathode, whereas the anions will move towards the anode.
Thus in electrolytic conduction mass is transferred in the form of ions.
Whereas, no such transfer of mass occur in metallic conduction. It is just the flow of electrons. 

 Which of the following statements is true about electrolytic conduction?

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. Occurs due to flow of electrons

  2. Occurs due to flow of ions

  3. Both of the above

  4. None of the above

Show answer
Correct Option: B
Explanation:

In an electrolytic solution when a voltage is applied across the electrodes dipped into the solution, the ions present in the electrolyte move. The cations move towards the cathode, whereas the anions move towards the anode and thus electric current flows through the electrolytic solution. Thus electrolytic conduction occurs because of the flow of ions.

Which of the following would produce a highly conductive aqueous solution?

metallic and electrolytic conduction electrolysis chemical reactions electrochemistry chemistry

  1. Cyclohexane

  2. Hydrochloric acid

  3. Benzene

  4. Sucrose

  5. Acetic acid

Show answer
Correct Option: B
Explanation:

Hydrochloric acid acid is a ionic compound which can easily dissociates into $H^+$ and $Cl^-$ ionsand gives high conductivity.