Explain how rusting of iron is envisaged | Class 12 Chemistry Chapter Electrochemistry, Electrochemistry NCERT Solutions

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter Electrochemistry. This page offers a step-by-step solution to the specific question from Exercise 1, Question 15: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 15:

Explain how rusting of iron is envisaged as setting up of an electrochemical cell.

Answer:

In the process of corrosion, due to the presence of air and moisture, oxidation takes place at a particular spot of an object made of iron. That spot behaves as the anode. The reaction at the anode is given by,

Fe(s) → Fe2+ (aq) + 2e-

Electrons released at the anodic spot move through the metallic object and go to another spot of the object.

There, in the presence of H+ ions, the electrons reduce oxygen. This spot behaves as the cathode. These H+ ions come either from H2CO3, which are formed due to the dissolution of carbon dioxide from air into water or from the dissolution of other acidic oxides from the atmosphere in water.

The reaction corresponding at the cathode is given by,

The overall reaction is:

Also, ferrous ions are further oxidized by atmospheric oxygen to ferric ions. These ferric ions combine with moisture, present in the surroundings, to form hydrated ferric oxide  (Fe2O3, x)H2O    i.e., rust.

Hence, the rusting of iron is envisaged as the setting up of an electrochemical cell.


Study Tips for Answering NCERT Questions:

NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Electrochemistry.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

Latest Blog Posts

Stay updated with our latest educational content and study tips

Government Jobs by Age Limit: Eligibility and Opportunities in 2026

Government jobs continue to be one of the most popular employment options in India because of their job security, regular salary, pension benefits, and promotion prospects. However, one of the most frequent doubts of aspirants is age eligibility. Countless candidates are discouraged from applying for Government positions – or even from preparing for them – … Read more

Read More

NEET & JEE Preparation Guide for State Board Students

After preparation for NEET and JEE, students inclined towards studying under state education boards find themselves a step behind the CBSE students. The syllabus, question pattern and level of idea of these national entrance exams varies widely from most state board syllabus. But with the correct approach, students taking the state board can hold their … Read more

Read More

Simple and Compound Interest Formulas with Questions

Interest is one of the most significant ideas in maths and financial calculations. It is very common in banking, loan applications, investments, saving account and competitive exams. Simple Interest and Compound Interest make it easier to find out how much more is earned and/or paid on a principal during the period of time. These Interest … Read more

Read More

Spoken English Course Topics for Beginners in 2026

In 2026, students, professionals, and job seekers must have a high level of spoken English. Spoken English is a beginner level course to enhance learners’ communication skills in English, their pronunciation, vocabulary, grammar structure and confidence in speaking English fluently. Today, the emphasis of spoken English courses is placed on actual conversations, everyday speech practice … Read more

Read More

Comments

  • Subham kratos
  • Dec 28, 2019

Very nicely explained


Add Comment

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 15: Explain how rusting of iron is envisaged as setting up of an electrochemical cell.....