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प्रश्न
Write scientific reasons.
Lemon or tamarind is used for cleaning copper vessels turned greenish.
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उत्तर
- Copper vessels turned greenish due to the formation of copper carbonate layer.
- The citric acid present in the lemon or tamarind neutralizes the basic copper carbonate and dissolves the layer.
- That is why tarnished copper vessels are cleaned with lemon or tamarind juice to give the surface of the copper vessel its characteristic lustre.
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संबंधित प्रश्न
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Explain why Iron sheets are coated with zinc during galvanization.
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Explain why, iron sheets are coated with zinc.
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Name five methods of preventing rusting of iron.
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Mention two uses of the following metals and non-metals
Iron
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| 2) Anodising | b) Silver plated spoons |
| c) Coating of tin on copper | |
| d) Coating of Zinc on iron |
Write the name.
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Method used to present corrosion of copper.
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Give the equation for the formation of rust.
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| SUBSTANCE | MELTING POINT (K) | ELECTRICAL CONDUCTIVITY | |
| SOLID | LIQUID/ AQUEOUS | ||
| A | 295 | Good | Good |
| B | 1210 | Poor | Good |
| C | 1890 | Poor | Good |
| D | 1160 | Poor | Poor |
Identify Ionic compounds from the above given substances.
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- protect it from sun.
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Ships suffer a lot of damage though they are painted.
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