The magnitude of surface tension of liquid depends on the attractive forces between the molecules. Arrange the following in increasing order of surface tension:
Water, alcohol (C2H5OH) and hexane [CH3(CH2)4CH3)].
Hexane [CH3(CH2)4CH3)] has weak London dispersion forces because it is a non polar molecule . But water and alcohol is polar molecule there exist H- bonding and dipole- dipole interaction. These forces are stronger than London force. Due to this water and alcohol has strong interaction between the molecules than hexane, Hexane has low surface tension than other two.
H-bonding is stronger in water than alcohol, so water has strong intermolecular attraction than alcohol. Increasing order of surface tension is - Hexane alcohol water