Surface Tension Question? - Liquid State (check my work)?

Question

Question: Rank the following in order of decreasing surface tension at a given temperature, and EXPLAIN your ranking:
(a) CH3OH (b) CH3CH3 (c) H2C(double bond)O

My Approach:
CH3OH, H2C(double bond)O, CH3CH3 --- My ranking

isn't it lesser surface tension when there is a Dispersion (London force)?

Answer 1

You ranking is correct. Be careful, thiough, about recklessly invoking London dispersion forces. I would have said that van der Waals forces explain a lot of the intermolecular attraction of something as heavy as ethane.