Rusting of iron is the most common example of corrosion. It is an oxidation process that occurs when iron is exposed to moisture and oxygen. It is a fundamental concept in Class 10 Chemistry.
Rust is soft, porous, and flaky. Unlike the tarnish on aluminium (which protects the metal underneath), rust constantly flakes off, exposing fresh iron to the air, eventually destroying the entire object.
The overall chemical equation for the rusting of iron is:
4Fe(s) + 3O₂(g) + 2xH₂O(l) → 2Fe₂O₃·xH₂O(s)
Where:
The 'x' in the formula of rust (Fe₂O₃·xH₂O) represents a variable number of water molecules of crystallization. The exact number of water molecules depends on the humidity and moisture present in the environment when the rust forms.
For rusting to take place, two conditions are absolutely essential:
Galvanisation is a widely used method to prevent rusting. It involves coating iron or steel objects with a thin layer of **Zinc (Zn)**. Zinc acts as a sacrificial barrier, corroding before the iron does.
विरंजक चूर्ण का रासायनिक सूत्र (Bleaching Powder Formula)
विरंजक चूर्ण (Bleaching Powder) का रासायनिक सूत्र (CaOCl2) जानें। Class 10 Chemistry के लिए इसका रासायनिक नाम (Calcium Oxychloride) और उपयोग समझें।
What Happens When Water is Poured on Calcium Oxide?
When water is poured on calcium oxide, slaked lime forms in an exothermic reaction. Equation: CaO + H₂O → Ca(OH)₂. Observations, uses, and FAQs explained.
Weak Acid and Weak Base: Definition and Examples
Learn the difference between strong/weak acids and strong/weak bases in Class 10-11 Chemistry. Includes examples and pH comparison.
Which of the Following is a Weak Acid? — Definition & Examples
Weak acids partially dissociate in water. Examples include acetic acid, carbonic acid, and citric acid. Learn the difference between weak and strong acids with FAQs.
Welding Fuel Gas — Acetylene and Other Gases Used in Welding
Acetylene (ethyne, C₂H₂) is the main welding fuel gas used in oxyacetylene welding. Learn the chemistry, flame temperature, and other welding gases with FAQs.
Turn this guide into revision flashcards, a practice exam, or an AI-generated podcast — free, no signup required.