as and when vs as soon as

as and when

conj

  • as soon as 

as soon as

conj

  • At the moment when; immediately after. 

  • Used other than figuratively or idiomatically: see as, soon. 

  • Used to indicate that the first action mentioned is as likely as, or is preferred to, the second action mentioned. 

prep

  • Used other than figuratively or idiomatically: see as, soon. 

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