what is the {temperature} for {calcium carbonate} has {density} as {2.7} ?
At what temperature does calcium carbonate have a density of 2.7?
What temperature is calcium carbonate that had a density of 2.7?
SELECT ?v WHERE { FILTER ( ?e = 2.7 ) . ?n property:temperature ?v . resource:calcium_carbonate property:density ?n . ?n property:density ?e }
select distinct ?value  where {
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#subject> <http://wikidata.dbpedia.org/resource/Q23767> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#predicate> <http://www.wikidata.org/entity/P2054> .
?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <2.7> .
?statement <http://www.wikidata.org/entity/P2076> ?value. 
} 

SELECT ?value WHERE { wd:Q23767 p:P2054 ?s . ?s ps:P2054 ?x filter(contains(?x , '2.7')) . ?s pq:P2076 ?value}