Question: which was the series ordinal  for ether which has  ionization energy as 9.53?
Paraphrase: With an ionized energy of 9.53, ether, has what numerical order?
SPARQL (Wikidata): SELECT ?value WHERE { wd:Q202218 p:P2260 ?s . ?s ps:P2260 ?x filter(contains(?x , '9.53')) . ?s pq:P1545 ?value}