Why the solution of aluminium sulphate in water is not clear
Aluminium sulphate when dissolved in water forms aluminium hydroxide and sulphuric acid.Since, aluminium hydroxide is insoluble in water, a clear solution is not obtained.
Al2(SO4)3 + 6H2O →2Al(OH)3 + 3H2SO4
Aluminium Aluminiumsulphate Hydroxide
The lack of clarity in a solution of aluminum sulfate in water is caused by the formation of aluminum hydroxide. When aluminum sulfate is dissolved in water, it undergoes ionization, resulting in the formation of aluminum ions (Al3+) and sulfate ions (SO4^2-). However, in the presence of water, the aluminum ions can react with hydroxide ions (OH-) from water to form insoluble aluminum hydroxide (Al(OH)3) precipitates.
The formation of precipitates causes the solution to become cloudy or turbid, reducing its clarity. These aluminum hydroxide particles are small and suspended in the solution, making the solution appear hazy. The extent of cloudiness in the solution depends on various factors such as the concentration of aluminum sulfate, temperature, and pH of the solution.
To obtain a clear solution of aluminum sulfate in water, you can try a few steps:
1. Increase agitation: Stir the solution vigorously to disperse the aluminum hydroxide precipitates. This might help in temporarily improving the clarity of the solution.
2. Adjust the pH: The formation of aluminum hydroxide is highly dependent on pH. Try adjusting the pH of the solution to a more acidic or basic level, using an acid or a base, respectively. This may prevent the formation of aluminum hydroxide and improve the clarity of the solution.
3. Filtration: If you need a clear solution, you can filter the solution using filter paper or a fine mesh filter to remove the suspended aluminum hydroxide particles. This will separate the solid precipitates from the solution, resulting in a clearer liquid phase.
It's important to note that even with these steps, achieving complete clarity may not be possible due to the nature of aluminum hydroxide. However, these methods can help improve the solution's clarity to some extent.