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प्रश्न
Name three methods by which hydrous substances can be made anhydrous.
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उत्तर
Three methods by which hydrous substances can be made anhydrous are:
- Heating under vacuum.
- Direct heating.
- Heating in dry or hot air.
- By using dehydrating/desiccating agents such as warm concentrated sulphuric acid.
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संबंधित प्रश्न
Give one word for the following statement:
A property due to which a substance absorbs water without dissolving.
The substance that can remove hydrogen and oxygen atoms in the ratio of 2:1(in the form of water) from the compound.
Complete the following table:
|
Common Name |
Chemical Name |
Formula |
Acid, base or salt |
Efflorescent, hygroscopic or deliquescent substance |
|
Solid caustic potash |
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|
|
|
Quick lime |
|
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|
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Oil of vitriol |
|
|
|
|
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Washing soda |
|
|
|
|
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Solid caustic soda |
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|
|
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Blue vitriol |
|
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Complete the statement by filling the blank with the correct word from the option.
Hygroscopic substance absorb moisture from the atmosphere & _______their original state.
Explain the following observation:
Why is fused calcium chloride or cone, sulphuric acid used in a desiccator?
Select the correct word from the words in option to complete the sentence:
Efflorescence occurs when the vapour pressure of the hydrated crystals is ____ than the vapour pressure of the atmospheric humidity.
Name or state the following:
A liquid hydroscopic substance.
Differentiate between the following:
Deliquescent salt and hygroscopic salt
The molecular formula of green vitriol is MgSO4.7H2O.
'A' is a blue coloured crystalline salt. On heating, it loses blue colour and to give 'B'. When water is added, 'B' gives back to 'A'. Identify A and B, write the equation.
