(a) Give one main difference between lyophilic anc lyophobic colloids.
(b) Explain
(i) A freshly formed precipitate of ferric hydroxide can be converted to a colloidal sol by shaking it with a small quantitiy of ferric chloride.

Give one main difference between lyophobic and lyphilic colloids.

Give two differences between lyophilic and lyophobic colloids.

On adding few drops of dilutie HCl or FeCl_(3) to freshly precipitated ferric hydroxide a red coloured colloidal solution is obtained. The phenomenon is know as

In a colloidal state, the particle size of he dispersed phase ranges between 10^(3) to 10^(6) pm and the colloidal sol is of heterogeneous nature. Depending upon the ease with which these sols are formed, the colloidal sols are cassified as lyophilic and lyophobic. THe stability of a colloidal sol is due to the presence of charge on the sol particles and the neutralisation of the same is known as coagulation or precipitation. The coagulationg power of the active ions of he electrolytes can be compared with the help of Hardy-Schulze Law. The protecting power of the lyophilic sols can be compared with the help of gold number. Lesser the value of gold number, more will be the protecting power of the lyophilic sol. On adding feq drops of dilute HCl to freshly precipitated ferric hydroxide, a red coloured colloidal sol is obtained. The phenomenon is Known as: