NCERT Solutions for Class 7 Science Chapter 6
Important NCERT Questions
7th Chapter 6 Physical and Chemical Changes
NCERT Books for Session 2022-2023
CBSE Board and State Board
Questions No: 9
Explain how painting of an iron gate prevents it from rusting.
Share
Painting an iron gate serves as a protective measure against rust formation by creating a barrier between the iron surface and external factors, primarily moisture and oxygen. Here’s how it prevents rusting:
1. Barrier Formation:
– Physical Barrier: The paint creates a physical barrier or protective layer over the iron surface, preventing direct contact with moisture and oxygen in the air, which are essential for the formation of rust.
2. Preventing Moisture Contact:
– Moisture Exclusion: By covering the iron surface with paint, moisture from the atmosphere is unable to directly interact with the iron. This hindrance inhibits the initiation of the rusting process, as moisture is a crucial factor for oxidation to occur.
3. Oxygen Isolation:
– Oxygen Prevention: The paint layer also acts as a shield against oxygen exposure. Oxygen is one of the key components needed for the oxidation reaction that leads to rust formation. By isolating the iron from direct contact with oxygen, the likelihood of rust formation decreases significantly.
4. Chemical Protection:
– Some paints contain additives or compounds that provide additional protection. These additives can act as corrosion inhibitors, enhancing the protective barrier against rusting.
5. Regular Maintenance:
– Regular inspection and touch-ups of the paint layer are essential. Damaged or chipped paint should be repaired promptly to maintain the protective barrier and prevent the iron from being exposed to moisture and oxygen.
In summary, painting an iron gate serves as a protective shield, creating a physical barrier that limits direct contact between the iron surface and elements like moisture and oxygen. This preventive measure inhibits the oxidation process, thereby significantly reducing the chances of rust formation and preserving the iron’s integrity and appearance.
For rusting, the presence of both oxygen and water (or water vapour) is required. The coat of the paint prevents direct contact of iron with air and oxygen and thus prevents it from rusting.
https://www.tiwariacademy.com/ncert-solutions/class-7/science/chapter-6/
For rusting, the presence of both oxygen and water (or water vapour) is required. The coat of the paint prevents direct contact of iron with air and oxygen and thus prevents it from rusting.