liquefaction vs uniting

liquefaction

noun
  • The liquid or semiliquid that results from this process. 

  • Process of being, or state of having been, made liquid (from either a solid or a gas) 

uniting

noun
  • The act by which things are united; the formation of a union. 

How often have the words liquefaction and uniting occurred in a corpus of books? (source: Google Ngram Viewer )