ELI5 Rubbing Alcohol - why is 70% better than 90%?

What makes 70% alcohol a better disinfectant than 90% alcohol? What is the pancake alcohol analogy? What is Isopropyl alcohol?   ... We explain like i'm five!     Thank you to the r/explainlikeimfive community as always and in particular the following users whose questions and comments formed the basis of this discussion: pixie_laluna, studentdoctor_kenobi, butterchest & okimintrigued To the ELI5 community that has supported us so far, thanks for all your feedback and comments. Send us an e-mail: [email protected]