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Hydrogen

Short Answer Type

131. Do you expect different products in solution when aluminium (III) chloride and potassium chloride are treated separately with:
(i) normal water (ii) acidifed water and (iii) alkaline water?

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132.

What is hard and soft water?

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Long Answer Type

133. What causes the temporary and permanent hardness of water?
Or
Distinguish clearly between temporary hardness and permanent hardness.
Or
What is hardness of water due to? What are its types?

901 Views

Short Answer Type

134.

Why does hard water not form lather with soap?

574 Views

Long Answer Type

135.

What are different methods used for softening of hard water?

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136. What is ‘demineralised water’ and how can it be obtained?

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137. Discuss the principle and method of softening of hard water by synthetic ion-exchange resins.
Or
What do you mean by synthetic ion-exchange resins?

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Short Answer Type

138.
How will you prepare a sample of temporary hard water from lime water? Write equation for the reactions involved.

Temporary hard water can be obtained by passing carbon dioxide in excess through lime water when calcium carbonate is first formed. It changes to soluble calcium bicarbonate by passing more carbon dioxide which imparts temporary hardness to water.