Give balanced equations to show how -

(a) Temporary hardness enters into water.

(b) Temporary hardness in water can be removed by boiling.

(c) Permanent hardness in water can be removed by addition of washing soda.

Select the correct answer from A, B, C, D & E for each statement given below:

A: Colloidal

B: Fused calcium chloride

C: Solvent

D: Suspension

E: Washing soda

1. The medium of dissolution which allows the solute to dissolve in it.

2. A solution which can pass through a filter paper but not through a semipermeable membrane

3. A monohydrate crystal.

4. A drying agent placed in desiccator.

5. A heterogenous mixture of undissolved particles in dispersion medium, visible to the naked eye.

Complete the statements by filling the blanks with the correct word from the bracket.

1. Solubility of most solids …………… (decreases/increases) with rise in temperature.

2. Kerosene & water form a …………… (miscible/immiscible) mixture.

3. Solubility of a solute is the …………… [minimum/maximum] amount of solute that will saturate 100 g. of water at t°C.

4. Hygroscopic substance absorb moisture from the atmosphere & …………… (do not change/change) their original state.

5. The ratio of hydrogen & oxygen in water is …………… (2:1/1:2)

Give reasons for the following:

1. All solutions are homogenous mixtures of a solute in a solvent.

2. Hardness in temporary water can be removed by boiling, but hardness in permanent hard water cannot.

3. Colloidal solutions exhibit brownian movement.

4. The percentage of oxygen, in air dissolved in water, is higher than the percentage oxygen in ordinary air.

5. Washing soda can be used to remove both temporary and permanent hardness in water.