Hardness of Water:Causes, Types and Treatments

Q.

Water that does not give lather with soap is water ______________ (hard water/soft water ).

Q.

Powdered ${\mathrm{CaCO}}_3$ reacts more rapidly than flaky ${\mathrm{CaCO}}_3$ because of?

Q.

Temporary hardness can be removed by which of the following process?

1. By boiling

2. By cooling

3. By addition of lime

4. By the addition of washing soda.

Q.

White sticky substance formed when soap is mixed with hard water is called ____________.

Q. Study the Venn diagram given below and identify the compounds X, Y, and Z from the given options.

1. X: $H_{2}S{O}_4$;
   Y: $C_{12}{H}_{22}{O}_{11}$;
   Z: $Ca(OH{)}_2$
2. X: $HN{O}_3$;
   Y: $C_2{H}_{5}OH$;
   Z: $C{H}_{3}COONa$
   
3. X: $Ca(OH{)}_2$;
   Y: HCOOH;
   Z: $C_{12}{H}_{2}6$
   
4. X: $H_{2}S{O}_4$;
   Y: $C{H}_{3}COONa$;
   Z: $C_2{H}_{5}OH$
   

Q. A painter wanted to white wash a house. She bought 10 kg of quick lime from the market and dissolved in 30 litres of water. On adding lime to the water, she noticed that the water started boiling even when it was not being heated. Give reason for her observation. Write the corresponding equations and name the product formed.

Q.

A house wife wanted her house to be white washed. She bought 10 kg of quick lime from the market and dissolved in 30 litres of water. On adding lime to the water, she noticed that the water started boiling even when it was not being heated. Give reason for her observation. Write the corresponding equations and name the product formed. [3 MARKS]