Join 60,000+ competitive exam aspirants
or with email
Your Cart
SubtotalтВ╣0
TotalтВ╣0
Examoogle тАв User тАв info@examoogle.com тАв EE-2024-8821
Chapter 1 of 12 тАв Page 1 of 248ЁЯФТ Protected PDF тАв Watermarked
Join 60,000+ competitive exam aspirants
Which of the following methods is NOT used for preventing iron from rusting?
Chrome plating
Painting
Galvanising
Heating
Heating
Heating is not a method used for preventing iron from rusting. Rusting is an oxidation process, and simple heating of iron in air typically promotes the formation of iron oxides (like scale) rather than acting as a protective barrier.
Heating is not a method used for preventing iron from rusting. Rusting is an oxidation process, and simple heating of iron in air typically promotes the formation of iron oxides (like scale) rather than acting as a protective barrier.
Think of a raincoat; painting and plating are like wearing a raincoat to stay dry, while heating is like standing in the middle of the rain and hoping you won't get wet.
P.G.C. тАФ Painting, Galvanising, Chrome plating are all 'Coverings' that prevent rust.
Fe+O2тАЛ+H2тАЛOтЖТFe2тАЛO3тАЛтЛЕxH2тАЛO тАФ The general chemical reaction for the formation of rust (hydrated iron(III) oxide)
ZnтЖТZn2++2eтИТ тАФ The oxidation of zinc in galvanisation which protects the iron cathode
Prevention methods like galvanising and painting work by creating a physical or electrochemical barrier between the iron surface and the environment (oxygen and moisture). Galvanising specifically uses sacrificial protection where zinc, being more reactive than iron, oxidizes first (ZnтЖТZn2++2eтИТ), while painting provides a simple coating to block contact with water and air.
Rusting requires both oxygen and moisture to occur.
Galvanising is the process of coating iron or steel with a thin layer of zinc.
Chrome plating provides a shiny, decorative, and corrosion-resistant finish.
Painting is the most common method for preventing rusting of iron objects like grills and gates.
Galvanising provides excellent long-term corrosion protection even if the coating is scratched.
Painting requires frequent maintenance as the layer can peel off or crack over time.
Galvanised iron pipes for water supply
Painted iron railings and structures
Rust is chemically referred to as hydrated iron(III) oxide.
Heating iron in the presence of oxygen actually accelerates the formation of an oxide layer, which is not protective against further corrosion.
D is correct тАФ Heating is a process that can actually promote oxidation or thermal damage rather than preventing the chemical process of rust formation.
When asked about rust prevention, look for methods that isolate the metal from oxygen and water; anything that involves energy input like 'heating' is usually a distractor in this context.
Get instant step-by-step AI explanations, full shift Previous Year Papers (SSC GD, RRB, SSC JE), and regional rank analysis on the official Examoogle App.
Free Download тАв 100K+ Aspirants