Salt Bridge and Electrochemical Cells

This video tutorial explores the role of the salt bridge in electrochemical cells, focusing on the zinc-copper cell. It explains how the salt bridge maintains charge neutrality and potential difference by allowing ion flow, preventing the cancellation of potential differences. The video also discusses the application of these concepts in commercial cells, such as alkaline storage cells and proton exchange membrane fuel cells.

What is the primary role of a salt bridge in an electrochemical cell?

• To separate the anode and cathode physically

• To increase the cell's voltage

• To conduct electrons between electrodes

• To maintain charge neutrality by allowing ion flow

Which substance is typically used in a salt bridge?

• Sodium chloride

• Calcium carbonate

• Potassium nitrate

• Magnesium sulfate

Why is a salt bridge considered a poor conductor of electrons?

• It is made of non-conductive materials

• It is designed to block electron flow

• It is too small to conduct electrons

• It only allows ion flow, not electron flow

In a zinc-copper cell, what happens to the electron concentration at the zinc electrode during operation?

• It remains constant

• It decreases

• It fluctuates randomly

• It increases

What problem arises when charge neutrality is violated in an electrochemical cell?

• The cell explodes

• The electrodes dissolve

• The potential difference is nullified

• The cell overheats

How does the salt bridge help maintain the potential difference in a cell?

• By allowing ions to flow in the opposite direction to electrons

• By allowing electrons to flow

• By increasing the concentration of reactants

• By physically separating the electrodes

What is the role of the ion conducting separator in an alkaline storage cell?

• To conduct electrons between electrodes

• To allow ion flow and prevent charge separation

• To increase the cell's voltage

• To physically separate the anode and cathode

In a proton exchange membrane fuel cell, what moves across the membrane?

• Water molecules

• Oxygen molecules

• H+ ions

• Electrons

What happens to H+ ions in a proton exchange membrane fuel cell?

• They are oxidized at the anode

• They move to the cathode and are reduced

• They remain at the anode

• They are converted into water

Which of the following is NOT a function of a salt bridge?

• Preventing charge separation

• Maintaining charge neutrality

• Conducting ions

• Increasing cell voltage