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Question
Explain concept with example/explain with the help of a balanced equation.
Corrosion
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Solution
- The process of slow degradation of the metals due to the attack of atmospheric gases, moisture, acids, etc. on the surface of metals is called corrosion.
- Iron reacts with moist air and a deposit of reddish substance (Fe2O3.H2O) is formed on it. This substance is called rust and the corrosion of iron is known as rusting.
- Carbon dioxide in moist air reacts with the surface of copper vessel. Copper loses its lustre due to formation of a greenish layer of copper carbonate (CuCO3) on its surface. This is called patination of copper.
- Various methods such as galvanizing, tinning, alloying, etc. are used to protect metals from corrosion.
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