Hello,

Hardy Schulze Rule tells that the required amount of electrolyte for the coagulation of a definite quantity of colloidal solution is dependent on the valency of the coagulating ion (which holds a charge that is opposite to the charge of colloidal particles) .

The ions of the electrolyte that are effective in coagulation are ones that can carry charge which is opposite to the particles . these are flocculating ions or coagulating ions . The greater is the valency of these ions , greater is the power to start the coagulation .

Hope this helps you !

Hardy Schulze Rules are as follows

1. Ions having opposite charge to the charge on colloid coagulate sol
2. Higher the charge on coagulating ion, higher is the coagulation power
3. Coagulation power of electrolyte is directly  proportional to the 6th power of the charge of coagulating ion.