Report Abuse. Yes pH is temperature dependent. So if you have water with a pH of 6.9 (very mildly acidic) at 12 C, and raise the temp up to about 22 C, the pH will reduce to about 6.7, which is more acidic. Jason, only pure water is neutral... most water you come across on a daily basis is not pure and doesn't have a pH of 7. derekbradley4000 · 8 years ago.