MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY MARTYN F. CHILLMAID / SCIENCE PHOTO LIBRARY
Acid reflux experiment. Acid reflux from the stomach can be neutralized by antacid. Here, the universal indicator has turned red in the presence of an acid. Colour changes will indicate changes in the acidity. For a sequence showing the changes as the acid is neutralised by the addition of an antacid, see images C010/9143-9145.
Model release not required. Property release not required.