pH measures how many free hydrogen ions (H⁺) are floating in a fluid. The more H⁺ there is, the more acidic the fluid. Your blood must stay very close to 7.4. So the body relies on buffers to keep it there. Push the pH around and see.
The pH scale & the ions
7.0pHNeutral
balanced H⁺ and OH⁻
Push it around
📷 Reference image
A real labeled figure to compare with the interactive above.
pH, Acids, Bases & Buffers — OpenStax, CC BY 3.0 (via Wikimedia Commons)
