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प्रश्न
You are given samples of three metals − sodium, magnesium and copper. Suggest any two activities to arrange them in order of their decreasing reactivities.
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उत्तर
Sodium, magnesium and copper can be arranged based on their reactivity with water. Sodium reacts violently with cold water because it is the most reactive of the three. Magnesium does not react with hot or cold water; it reacts with only steam. Copper does not react even with steam and it is the least reactive of the three.
These three metals can be arranged based on their reactivity with a dilute acid as well. Sodium reacts with dilute hydrochloric acid violently. Magnesium reacts with dilute hydrochloric acid but less rapidly than sodium. Copper is the least reactive and it does not react with dilute hydrochloric acid.
So the order of their decreasing reactivity is sodium > magnesium > copper.
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संबंधित प्रश्न
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| A | No reaction | Displacement | ||
| B | Displacement | No reaction | ||
| C | No reaction | No reaction | No reaction | Displacement |
| D | No reaction | No reaction | No reaction | No reaction |
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Fill in the following blank with suitable word:
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| Malleable | Yes | No | No | Yes |
| Ductile | Yes | No | No | Yes |
| Electrical conductivity | Yes | Yes | Yes | No |
| Melting Point | High | Low | Low | High |
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