【Daily Question】Theoretical Foundation 2020.08.16
Thread Content
Multiple-choice question: Which of the following statements about the salt bridge is incorrect? ( ) A. Electrons flow through the salt bridge； B. The electrolyte in the salt bridge can neutralize the excess charges in the two half-cells ； C. It can maintain the progress of redox reactions ； D. The electrolyte in the salt bridge does not participate in the battery reaction. Answer: A. Hint: An additional reward will be given to those who can explain the solution process; the answer can be seen in the response
D. The electrolyte in the salt bridge does not participate in the battery reaction
A salt bridge is usually a U-tube filled with a saturated potassium chloride solution containing gelatin; its function is to maintain electrical neutrality and form a closed circuit. During a galvanic cell reaction, ions in the solution gain or lose electrons, resulting in an excess of positive or negative charges in the half-cells. Ions in the salt bridge diffuse into both half-cells to act as a neutralizing agent ； At the same time, a current is generated in the salt bridge, forming a closed circuit that ensures the progress of the galvanic cell reaction, that is, it maintains the occurrence of redox reactions ； The electrolyte in the salt bridge participates in the battery reaction.
D. The electrolyte in the salt bridge does not participate in the battery reaction
Choose A. A. Incorrect. The function of a salt bridge is to transfer ions; molecules and electrons cannot pass through it. B. Correct. By transferring ions, the salt bridge eliminates the excess charge in the two half-cells. C. Correct. If excess charge accumulates in the two half-cells, the battery reaction will stop quickly. D. Correct. A salt bridge is usually filled with a saturated KCl solution, and KCl does not participate in redox reactions.
A D-salt bridge is usually a U-tube containing a saturated potassium chloride solution with gelatin, and its function is to maintain electrical neutrality and form a closed circuit. During a galvanic cell reaction, ions in the solution gain or lose electrons, resulting in an excess of positive or negative charges in the half-cells. Ions in the salt bridge diffuse into both half-cells to act as a neutralizing agent ； At the same time, a current is generated in the salt bridge, forming a closed circuit that ensures the progress of the galvanic cell reaction, that is, it maintains the occurrence of redox reactions ； The electrolyte in the salt bridge participates in the battery reaction