47.7 MB (4.3 MB compressed)
5136 x 3243 pixels
43.4 x 27.4 cm ⏐ 17.1 x 10.8 in (300dpi)
GIPHOTOSTOCK / SCIENCE PHOTO LIBRARY GIPHOTOSTOCK / SCIENCE PHOTO LIBRARY
Universal indicator added to several test tubes containing solutions with varying pH values. Universal indicator changes its colour depending on the pH of the solution. Red indicates a strong acid, yellow/orange indicates an acid, green is neutral, blue indicates an alkali, and purple indicates a strong alkali.
Model release not required. Property release not required.