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प्रश्न
Answer the following question:
Grills of doors and windows are always painted before they are used? Give reason.
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उत्तर
- Grills of doors and windows are generally made up of iron metal.
- Before painting, iron metals are in direct contact with the moisture in atmosphere.
- Thus chemical reaction between iron and oxygen from the air takes place to form a reddish-brown coloured substance (ferric oxide) called rust which damages the grill.
- Painting prevents corrosion as it prevents iron metal from coming in contact with moisture and oxygen from the atmosphere.
Hence, the grills of doors and windows are always painted before they are used.
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संबंधित प्रश्न
Describe the process of neutralization with the help of an example.
Sodium hydroxide and hydrochloric acid neutralise each other and form salt and water.
What do you observe when an acid is added to a basic solution.
FILL IN THE BLANK
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Classify the following substances into Acidic, Basic, and Neutral groups.
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Answer the following:
What is corrosion? Do gold ornaments corrode? Justify.
Differentiate between the following:
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Explain the neutralization reactions in our daily life.
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Neutralisation reaction is a ______.
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Write a note on:
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