Laboratory Notes: Phenolphthalein/NaOH agar cube experiment
Investigating the effect of cell size on diffusion (absorption) rate (speed) is a common investigation carried out by secondary students. It is modelled with a simple experiment using different-sized cubes of agar containing a pH indicator.
These laboratory notes provide a method for producing Phenolphthalein - sodium hydroxide agar and directions for conducting the experiment. Safety considerations and waste disposal instructions are also included.