A pH meter measures a pH or the acidity/alkalinity of substances. Most pH meters rely on a glass electrode that measures the number of hydrogen ions in the solution. Usually, pH meters need to be ...

The color of hydrangea flowers can change from pink to purple and blue by tweaking the soil. How do other plants react to those changes? Sydney Kozak explored just that. Her project, “Does changing ...

Understanding the nature of pH has bedeviled beginning (and not-so-beginning) chemistry students for nearly as long as chemistry has had students. It all seems so arbitrary, being the base-10 log of ...