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Question
Give a reason for the following:
Heating a hydrated copper sulphate crystal is deemed a chemical change.
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Solution
Heating hydrated copper sulphate crystal is a chemical change as on adding water drops on white powder of CuSO4 (amorphous) colour restores but geometric shape is not restored i.e. after heating new composition is found to give crystalline shape.
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RELATED QUESTIONS
Give one word for the following statement:
A substance which does not contain water .
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Anhydrous substance
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Common Name |
Chemical Name |
Formula |
Acid, base or salt |
Efflorescent, hygroscopic or deliquescent substance |
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Solid caustic potash |
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(a) Washing soda
(b) Gypsum
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(d) Epsom salt
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State which crystal from (a) to (e) is a pentahydrate.
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Explain the following observation:
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