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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
Iron is
(a) More reactive than zinc
(b) More reactive than aluminium
(c) Less reactive than copper
(d) Less reactive than aluminium
Samples of four metals A, B, C and D were taken and added to the following solution one by one. The results obtained have been tabulated as follows.
| Metal | Iron (II) sulphate | Cooper (II) sulphate | Zinc sulphate | Silver nitrate |
| 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 |
Use the Table above to answer the following questions about metals A, B, C and D.
- Which is the most reactive metal?
- What would you observe if B is added to a solution of copper (II) sulphate?
- Arrange the metals A, B, C and D in the order of decreasing reactivity.
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.
The reaction of an iron nail with copper sulphate solution is ........... reaction.
(a) Combination
(b) Displacement
(c) Double displacement
(d) Decomposition
What changes in the colour of iron nails and copper sulphate solution do you observe after keeping the iron nails dipped in copper sulphate solution for about 30 minutes?
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?
Write one reaction in which aluminium oxide behaves as a basic oxide and another in which it behaves as an acidic oxide.
Write the chemical equation of the reaction which takes place when iron reacts with dilute sulphuric acid. What happens when the gas produced is ignited with a burning matchstick?
Write the equation for the reaction of:
Zinc with dilute hydrochloric acid.
Name the products formed in the given case. Also indicate the physical states of all the substances involved.
The elements whose oxides can turn phenolphthalein solution pink are ______.
You are given a solution of AgNO3. Which of the following do you think cannot displace Ag from AgNO3 solution?
The least reactive metal among the following is:
The elements whose oxides can turn litmus solution blue are ______.
Name a metal for the given case:
It does not react with cold as well as hot water but reacts with steam.
Name a metal for the given case:
It does not react with any physical state of water.
Write the chemical equation for the following reaction:
Cinnabar is heated in the presence of air.
Aluminium is used for making cooking utensils. Which of the following properties of aluminium are responsible for the same?
- Good thermal conductivity
- Good electrical conductivity
- Ductility
- High melting point
