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प्रश्न
When calcium metal is added to water, the gas evolved does not catch fire but the same gas evolved on adding sodium metal to water catches fire. Why is it so?
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उत्तर
Sodium is more reactive than calcium. The reaction between sodium and water produces a large amount of heat, which causes the evolved hydrogen to burn and catch fire. But in the reaction between calcium and water, no heat is produced and hence the evolved hydrogen does not catch fire.
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संबंधित प्रश्न
Write the electron-dot structures for sodium, oxygen and magnesium.
A student added few pieces of aluminium metal to two test tubes A and B containing aqueous solutions of iron sulphate and copper sulphate. In the second part of her experiment, she added iron metal to another test tubes C and D containing aqueous solutions of aluminium sulphate and copper sulphate.
In which test tube or test tubes will she observe colour change? On the basis of this experiment, state which one is the most reactive metal and why.
From amongst the metals sodium, calcium aluminium, copper and magnesium, name the metal:
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(ii) another which does not react even with steam.
Name the metal which has been placed at the bottom of the reactivity series.
Name the metal which has been placed at the top of the reactivity series.
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Fill in the following blank with suitable word:
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Name one metal more reactive and another less reactive than hydrogen.
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(a) K
(b) S
(c) P
(d) Kr
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