[defencegrid]

Hi.  I have a book that says to prepare a solution of Iron (III) Chloride you need to dissolve the solid in water and add 5ml of concentrated HCL and make up to 1 litre with water.  Just wondering what is the purpose of the HCL?

Iron (III) Nitrate it similar, it says to add 5ml of 2M Nitric Acid and for Iron (III) Sulphate it says to add 0.1M Sulphuric Acid.   

[AWK]

Fe(III) salts easily hydrolyse. Acids prevent from hydrolysis.

[defencegrid]

Fe(III) salts easily hydrolyse. Acids prevent from hydrolysis.

I see.  So how does the acid prevent the hydrolysis?

[AWK]

Wite equation of hydrolysis of Fe(H₂O)₆³⁺ ion