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प्रश्न
Answer the following question:
What is corrosion? Do gold ornaments corrode? Justify.
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उत्तर
- The slow process of decay or distinction ions of a metal due to the effect of air, moisture, acids, alkalies, or other chemicals on it is called corrosion.
- Ordinarily, gold ornaments do not get corroded.
- Gold is one of the least reactive metals. It does not react with air, moisture, sweat, or ordinary pollutants in air or water. Hence, it does not get corroded.
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संबंधित प्रश्न
What is an alloy?
Tinning : Tin : : Galvanizing : _________
Explain the term corrosion.
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Explain how painting of an iron gate prevents it from rusting.
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Name any three objects (or structures) which are gradually damaged by the corrosion of iron and steel.
The chemical reaction involved in the corrosion of iron metal is that of ______.
What is meant by galvanisation? Why is it done?
State two conditions for the rusting of iron.
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The corrosion of iron is called ______.
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What are the constituents of stainless steel?
A common metal which is highly resistant to corrosion is ______.
In stainless steel alloy, iron metal is mixed with ______.
Name the metal which is a constituent of plant pigment?
What is corrosion? What are necessary conditions for corrosion?
State under what conditions corrosion is faster ?
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Reaction on anode region :
`F_e(s) → Fe^(2+) (aq) +2e^-`
Reaction on anode region :
`O_2(g) + 4H^+(aq) +............................ → 2H_2 O (l) `
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`2Fe_(3+) (aq) + 4H_2O(l) → ................. + 6H_+(aq) `
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Write scientific reason.
Anodization method is useful for prevention of the corrosion of the aluminium.
Write scientific reason.
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Corrosion
What is rust?
Observe the following diagram and write answers.
- Name the method.
- Explain the method.
- Give two examples of this method.
Give an example of a chemical reaction for the following situation:
Sound is produced
