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Question
The sticky substance formed when soap is added to hard water is ______.
Solution
The sticky substance formed when soap is added to hard water is scum.
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RELATED QUESTIONS
What do you observe when Blue vitriol is heated?
Water turns the colour of anhydrous copper sulphate .................
Give the names and formulae of two substances
Anhydrous substance
Complete the following table:
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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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Oil of vitriol |
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Washing soda |
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Solid caustic soda |
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Blue vitriol |
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What are hydrous substances? Explain with examples.
Name three methods by which hydrous substances can be made anhydrous.
Differentiate between hydrated and anhydrous crystals with examples. State three defined changes that occur when hydrated copper sulphate is heated.
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.
Give a reason for the following:
Heating a hydrated copper sulphate crystal is deemed a chemical change.
Match the following
| 1. | Blue vitriol | CaSO4.2H2O |
| 2. | Gypsum | CaO |
| 3. | Deliquescence | CuSO4.5H2O |
| 4. | Hygroscopic | NaOH |
