The Kilcher Homestead is a 600 acre Pioneer Homestead that has been protected for perpetuity via a ConservatIon Easement. The Kilcher Family has also preserved the Historic Cabin and site as a LIving Museum.
Yes, negative pH is possible, but not in water as a solvent. The range of pH in water is 0 to 14 (to be more precise, it is -1.7 to 15.7, but for simplicity's sake, we start with the usual values.) Thus, what pH indicates is the ability of the acid to form H3O+, which can then donate a proton.
Substances with lower, or more acidic values, include lemons (2.2), wine and beer (4.0) and battery acid (1.0). Substances with higher, or more basic, pH values include bleach, as well as ammonia (11.0) and human blood (7.4). Bleach can be considered extremely basic at pH 12, and should not be allowed to contact bare skin.