Question

If you are going to see which food dye diffuses fastest in water. Which variables do you measure How will you do this?

Answer 1

You should be searching for your independent variable, and think about every variable to keep the same. The only thing that should be changing between separate experiments would be the type of food dye, you keep the amount of dye used, the place you're distributing to, the location, temp... the list goes on. Your dependent variable is the outcome: Which food dye diffuses first.