Explain why some oil spreads uniformly on water when others float as drops

cbse
propertiesoffluids

#1

The force of surface tension of some oil is less than surface tension of water. When such oil are dropped on the surface of waiter, they are pulled in all water and as such they spread uniformly on water. In the case of other oils, whose surface tension is equal to or greater than that of water, they float as drops on water.