Effect of Temperature on Salt Solubility

Aluminium Potassium Alum. Put about 2 g of aluminium potassium alum into a test tube containing 3 ml of water. Does the alum dissolve in this amount of water in the cold If it doesn t, heat the contents of the tube almost to boiling. What is observed Let the solution cool. What happens How does the solubility of the alum change with a change in the temperature  

Sodium Chloride. Dissolve about 2 g of sodium chloride in 3 ml of water with heating. Pour the transparent hot solution into a dry test tube. What do you observe when the solution cools  

Calcium Acetate. Pour a small amount of a saturated calcium acetate solution into a dry test tube and heat it. Next cool the solution with a stream of water from a faucet. What is observed  

Find the values of the solubility (Appendix 1, Table 1) of alum, sodium chloride, and calcium acetate, and draw curves of their temperature dependence, laying off the temperature along the axis of abscissas and the concentration of a saturated solution along the axis of ordinates. 

Acquaint yourself with the appearance of aluminium potassium alum, sodium chloride, and calcium acetate crystals using a microscope. To do this, transfer a drop of the relevant solution containing a few crystals onto a slide. Cover the liquid with a cover glass and place the preparation on the microscope stage. Draw the shape of the crystals. 

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