What is meant by cathodic protection? (a) Steel is coated with a layer of paint. (b) Iron in steel is oxidized to form a protective oxide coating. (c) Steel is coated with zinc because zinc is more easily oxidized than iron. (d) A strip of magnesium is attached to steel because the magnesium is more easily oxidized than iron.

검증된 단계별 안내

Understand the concept of cathodic protection: It is a technique used to prevent corrosion of a metal surface by making it the cathode of an electrochemical cell.

Identify the role of a sacrificial anode: In cathodic protection, a more easily oxidized metal (sacrificial anode) is used to protect the metal of interest (cathode).

Analyze the options: Determine which option involves using a more easily oxidized metal to protect steel.

Option (c) involves coating steel with zinc, which is more easily oxidized than iron, providing cathodic protection.

Option (d) involves attaching a strip of magnesium to steel, where magnesium is more easily oxidized than iron, also providing cathodic protection.

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Cathodic Protection

Cathodic protection is a technique used to prevent corrosion of metal surfaces, particularly in structures like pipelines and ships. It involves making the metal surface the cathode of an electrochemical cell, which reduces the oxidation process that leads to corrosion. This can be achieved through sacrificial anodes or impressed current systems.

Sacrificial Anodes

Sacrificial anodes are metals that are more reactive than the metal they are protecting, such as zinc or magnesium. When attached to a structure like steel, these anodes corrode preferentially, thereby protecting the steel from oxidation. This method is commonly used in marine applications and underground pipelines.

Oxidation and Reduction

Oxidation and reduction are chemical processes that involve the transfer of electrons between substances. Oxidation refers to the loss of electrons, while reduction refers to the gain of electrons. In the context of cathodic protection, the metal being protected (like iron in steel) is reduced, preventing it from oxidizing and corroding.