The pH scale ranges from 0 to 14.
by Harry Sorensen
(Qld Australia)
Your notes on pH start with
The pH scale ranges from 0 to 14.
This is false.. (but often stated in bad chemistry texts )
10 molar hydrochloric acid has pH of -1
a cold saturated ammonia solution has high pH
I agree that for body pH the range 5 to 8 is practical.
Check the definition of pH scale as stated by its inventor Sorensen