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प्रश्न
Why are metals called electropositive elements?
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उत्तर
Metals are known as electropositive elements because they can form positive ions by losing electrons.
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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’.
Which gas is produced when dilute hydrochloric acid is added to a reactive metal?
What would you observe when zinc is added to a solution of iron (II) sulphate? Write the chemical reaction that takes place.
Show the formation of Na2O by the transfer of electrons.
You must have seen tarnished copper vessels being cleaned with lemon or tamarind juice. Explain why these sour substances are effective in cleaning the vessels.
From amongst the metals sodium, calcium, aluminium, copper and magnesium, name the metal:
- which reacts with water only on boiling, and
- 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.
Magnesium liberates ______ gas on reacting with hot boiling water.
What is the nature of the oxide Na₂O? What happens when it is dissolved in water? Write the chemical equation of the reaction involved.
Name two metals (other than zinc and iron) which can displace hydrogen from dilute hydrochloric acid?
What is the action of water on sodium ? Write equation of the chemical reaction involved.
Write one reaction in which aluminium oxide behaves as a basic oxide and another in which it behaves as an acidic oxide.
Hydrogen is not a metal but still it has been assigned a place in the reactivity series of metals. Why?
Metal A burns in air, on heating, to form an oxide A2O3 whereas another metal B burns in air only on strong heating to form an oxide BO. The two oxides A2O3 and BO can react with hydrochloric acid as well as sodium hydroxide solution to form the corresponding salts and water.
(a) What is the nature of oxide A2O3?
(b) What is the nature of oxide BO?
(c) Name one metal like A.
(b) Name one metal like B.
If A, B, C, D, E, F, G, H, I, J and K represent metals in the decreasing order of their reactivity, which one of them is most likely to occur in a free state in nature?
Choose the correct alternative and rewrite the following:
Reaction of iron nails whith copper sulphate solution is an example of _____________________
Metals are generally hard. Which of the following metals is an exception and can be cut with a knife?
