Impasivity or Impassivity: How To spell?
The word Impasivity is misspelled against Impassivity, a noun meaning "The quality of being insusceptible of feeling, pain, or suffering; impassiveness."
Impassivity has double "ss" is mispronounced as "s"Remember double 'SS' in between the strings impa & ivity which should not be misspelled with single 'S'
Wrong Spelling:  impa-s-ivity  Correct Spelling:  impa-ss-ivity 
Find more wrongly spelled words of Impassivity to spell it well.