# Investigatory Project on Diffusion of Solids in Liquids

Investigatory Project and Viva Questions on Diffusion of Solids in Liquids (Class 12)

The process of intermixing of substances when they are brought into contact with each other is called diffusion. Diffusion occurs rapidly in the case of gases. In the case of liquids it is less rapid and solids do not show this property when they are brought into contact. However, diffusion of solids occurs slowly in liquids in which they are soluble. The speed of diffusion depends on (a) temperature (b) size of the particles and (c) the mass of the particles.

Aim

The aim of this investigatory project is to study the effect of temperature on rate of diffusion of a solid in a liquid by taking crystals of copper sulphate.

Materials and Requirements

250 mL beakers, Crystalline copper sulphate, Distilled water, Ice, Stop watch etc.

Procedure

Take 5g each of CuSO4. 5H20 in three 250 mL beakers. Pour 100 mL of distilled water into one of the beakers, 100 mL ice water into the second beaker and 100mL hot water into the third beaker. Cover all the three beakers with watch glasses. Note the temperature of each. Observe the development of blue colour (due to diffusion). Record the time taken for the complete dissolution and diffusion of CuSO4 in all the three cases.

 No. Temperature Time taken in minute 1 2 3 Cold water Distilled water Hot water - - -

It is found that the diffusion occurs most readily in the hot solution.

Conclusion

The rate of diffusion of a solid in a liquid is directly proportional to temperature.

VIVA QUESTIONS ON DIFFUSION OF SOLIDS IN LIQUIDS

1. What is diffusion?

Ans: Intermixing of different substances when they are brought into contact with each other is called diffusion

2. Which type of substance has maximum diffusion?

Ans: Gases have maximum diffusion.

3. What are the factors which influence diffusion?

Ans: The rate of diffusion depends on the temperature, size of particles and the mass of particles.

4. Explain effect of temperature on rate of diffusion of a solid in a liquid?

Ans: Here when the temperature increases, the rate of diffusion also increases.

5. What colour is developed when copper sulphate is dissolved in water?

Ans: Blue

6. Equal masses of crystalline copper sulphate are added to equal volumes of water taken in two beakers which are kept at two different temperatures. Which water gets the blue colour earlier?

Ans: Water which has higher temperature