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प्रश्न
Give reason:
Sodium, potassium and lithium are stored under oil.
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उत्तर
- All three metals react with water, producing a lot of heat. As a result, hydrogen evolves and catches fire.
- They cannot be kept in the air because air contains moisture or water vapours. They are kept under kerosene to avoid contact with both air and water.
संबंधित प्रश्न
Name two metals which will displace hydrogen from dilute acids, and two metals which will not.
Diamond : electric insulator : : _______ : electric conductor
Which of the following oxide(s) of iron would be obtained on the prolonged reaction of iron with steam?
Which of the following metals liberate hydrogen with 5% HNO3?
(i) Cu
(ii) Zn
(iii) Mn
(iv) Mg
Which one of the following metals does not react with cold as well as hot water?
Which of the following oxide(s) of iron would be obtained on prolonged reaction of iron with steam?
Silver articles become black on prolonged exposure to air. This is due to the formation of
Stainless steel is very useful material for our life. In stainless steel, iron is mixed with
If copper is kept open in air, it slowly loses its shining brown surface and gains a green coating. It is due to the formation of
When a metal X is treated with cold water, it gives a basic salt Y with molecular formula XOH (Molecular mass = 40) and liberates a gas Z which easily catches fire. Identify X, Y and Z and also write the reaction involved.
Which of the following reacts with cold water vigorously?
Material: Copper wire, Iron nail, Beaker or Big test tube.
Chemicals: Ferrous Sulphate and Copper Sulphate Solution.
- Which reaction you will study with the help of the above material and solutions? Draw the diagram of the experiment arrangement.
- How do you identify that the reaction is carried out?
- Which type of reaction did you observe?
Answer the questions based on the figure below:
- Which experiment setup is demonstrated in the figure?
- What do you conclude after the reactions? Name reaction.
Keerti added dilute Hydrochloric acid to four metals and recorded her observations as shown in the table given below:
| Metal | Gas Evolved |
| Copper | Yes |
| Iron | Yes |
| Magnesium | No |
| Zinc | Yes |
Select the correct observation(s) and give chemical equation(s) of the reaction involved.
Select the appropriate state symbols of the products given as X and Y in the following chemical equation by choosing the correct option from table given below:
\[\ce{Zn_{(s)} + H_2SO_{4(l)} ->ZnSO_{4(X)} + H_{2(Y)}}\]
