Diffusion Rate Practical

What are the dependant variables in this experiment?

Mass, time, volume, temperature, length

What is the independent variable?

The pH

How can the effect of surface area to volume ratio on diffusion be measured?

Measuring the time taken for an entire agar cube to change colour, or the distance traveled in a specified time

How is this experiment set up?

Different sized agar cubes containing universal indicator are placed inside boiling tubes containing hydrochloric acid