Ref: https://edurev.in/question/687449/Needed-a-Document-for-what-is-rusting-Related-Chapter-Notes-2-Chapter-6-Physical-Chemical-Changes-S
What is Rust?
When iron is exposed to water or air over a period of time, the iron reacts with oxygen in the presence of moisture to form a reddish-brown chemical compound, iron oxide. This is referred to as rust. So chemically, rust is hydrated iron(III) oxide or Fe2O3.nH2O. The chemical equation for the same is given by:
4Fe(OH)2 + O2 + xH2O → 2Fe2O3.(x+4)H2O
Iron reacts very readily with oxygen. This is one of the reasons as to why it is rare to find pure iron in nature.
Factors Affecting Rusting
There are several factors that assist and accelerate the process of rusting. Some of them are:
Why Rust Prevention?
Rusting makes iron flaky and friable and decreases its intended usage period. The strength, appearance and permeability degrade which leaves the rusted iron useless. A considerable amount of damage is done by rusting every year, which includes damaging of cars, grills, buses, railings, sinking of ships, falling of bridges, deterioration of statues, etc. Huge sums of money is spent for the replacement and repair of these damages. Thus, it is important to take steps to prevent iron from getting rusted.
Preventive Measures
As we have seen earlier, the prime cause of rusting is the exposure of iron to water and air. So, if we don’t let the surface of iron to come in direct contact with them, we can prevent rusting. Some effective measures used to prevent rusting are:
Galvanisation of Iron
1. What is rusting and how does it occur? |
2. What are the factors that affect the rusting of iron or steel? |
3. How can rusting be prevented? |
4. Can rusting occur in the absence of oxygen? |
5. Does rust affect the structural integrity of iron or steel? |
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