Give five important applications of colloids in home and industry.

Explanation

The different applications of colloids are as follows:
i) Purification of drinking water : Water containing suspended impurities get settled at the bottom of tank when alum is added. Alum coagulates the impurities and make water free from impurities. ii) Formation of medicines : Large number of medicines are prepared in the form of emulsions. iii) Cleansing action of soap : The mechanism of cleansing action of soap is also based on the formation of colloids. iv) Industrial products : Rubber, graphite, cement, paints, inks etc., are all colloidal solutions. v) Tanning: The animal hide contains positively charged particles and tannin contains negatively charged colloidal particles. When positively charged animal hide is soaked in negatively charged tannin, mutual coagulation takes place. This process is used to hardening the leather and known as tanning.