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प्रश्न
Why is an iron grill painted frequently?
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उत्तर
To prevent rusting of iron substances, they are painted frequently. Iron is a reactive metal that starts corroding in the presence of air (oxygen) and water (moisture). Iron reacts with oxygen in moist air, forming a brown, flaky layer of iron oxide (rust) on its surface. This is called rusting. This rust causes significant damage to iron objects by weakening them. Therefore, an iron grill is painted frequently to prevent corrosion.
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संबंधित प्रश्न
Tinning : Tin : : Galvanizing : _________
Which metals do not corrode easily?
What is corrosion?
Explain why, when a copper object remains in damp air for a considerable time, a green coating is formed on its surface. What is this process known as?
A metal X which is resistant to corrosion is produced by the electrolysis of its molten oxide whereas another metal Y which is also resistant to corrosion is produced by the reduction of its oxide with carbon. Metal X can be used in powder form in thermite welding whereas metal Y is used in making cathodes of ordinary dry cells.
- Name the metals X and Y.
- Which of the two metals is more reactive: X or Y?
- Name one ore or metal X. Also write its chemical formula.
- Name one ore of metal Y. Also write its chemical formula.
- Name one alloy of metal X and one alloy of metal Y.
Four metals P, Q, R and S are all obtained by the reduction of their oxides with carbon. Metal P is used to form a thin layer over the sheets of metal S to prevent its corrosion. Metal Q is used for electroplating tiffin boxes made of metal S whereas metal R is used in making car batteries. Metals Q and R form an alloy called solder. What are metals P, Q, R and S? How have you arrived at this conclusion?
Mention two uses of the following metals and non-metals
Iron
Bronze is an alloy of ______.
What is corrosion? What are necessary conditions for corrosion?
Observe the following picture a write down the chemical reaction with the explanation.
Give a reason why rust turns moist red litmus blue.
Find the odd one out and give its explanation.
Find the odd one out and give its explanation.
Write the name.
An alloy of copper and tin-
Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
What is rust?
Galvanisation is a method of protecting iron from rusting by coating it with a thin layer of ____________.
Alloys are homogeneous mixtures of a metal with a metal or non-metal. Which among the following alloys contain non-metal as one of its constituents?
Explain the following:
Lime water turns milky on passing carbon dioxide gas into it.
Explain the chemical reactions in rusting of iron.
