What is the group IB flammable liquid with min surface tension whose instance of chemical compound?
select ?ent where { ?ent wdt:P31 wd:Q21009055 . ?ent wdt:P3013 ?obj . ?ent wdt:P31 wd:Q11173 } ORDER BY DESC(?obj)LIMIT 5 
class ib flammable liquid: Q21009055 chemical compound: Q11173