What is the {polyatomic cation} for {conjugate acid} of {ammonia}
What is ammonia's polyatomic cation?
What is the polyatomic cation of ammonia?
SELECT DISTINCT ?i WHERE { resource:Ammonia property:conjugate_acid ?i . ?i rdf:type ontology:polyatomic_cation }
select distinct ?obj where { ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q4087> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P4147> . ?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> ?obj . ?obj <http://www.wikidata.org/entity/P31> <http://wikidata.dbpedia.org/resource/Q55511472> } 
 select distinct ?obj where { wd:Q4087 wdt:P4147 ?obj . ?obj wdt:P31 wd:Q55511472 } 
ammonium cation