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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
‘E’ is an element which reacts with oxygen to form an oxide E2O. An aqueous solution of E2O turns red litmus blue, so:
i. What is the nature of oxide E2O ?
ii. Write the name of element ‘E’.
Differentiate between metal and non-metal on the basis of their chemical properties.
Complete and balance the following equation:
Na2O + H2O →
Fill in the following blank with suitable word:
Ordinary aluminium strips are not attacked by water because of the presence of a layer of ................. on the surface of aluminium.
With the help of examples, describe how metal oxides differ from non-metal oxides.
What type of oxides are formed when non-metals react with oxygen? Explain with an example.
How do non-metals react with hydrogen? Explain with an example.
What happens when magnesium reacts with very dilute nitric acid? Write an equation for the reaction involved.
Give one example, with equation, of the displacement of hydrogen by a metal from an acid.
Name two metals (other than zinc and iron) which can displace hydrogen from dilute hydrochloric acid?
Name another metal oxide which behaves like aluminium oxide.
What happens when a metal reacts with dilute hydrochloric acid? Explain with the help of an example.
Write the equation for the reaction of Zinc with dilute hydrochloric acid.
Name the products formed. Also indicate the physical states of all the substances involved.
Zinc oxide is a metal oxide. Which of the following term best describes the nature of zinc oxide:
(a) an acidic oxide
(b) a basic oxide
(c) an amphoteric oxide
(d) a neutral oxide
Which one of the following four metals would be displaced from the solution of its salt by the other three metals?
(a) Zn
(b) Ag
(c) Cu
(d) Mg
Name a metal which does not react with cold as well as hot water but reacts with steam.
Metals are generally hard. Which of the following metals is an exception and can be cut with a knife?
Metals are generally solid. Which of the following metals is in the liquid state at room temperature?
Why is acidified water considered to be a good conductor of electricity?
