I answered the discussion questions in the video already, but I will go through them again through text.
Why do you thin the food coloring didn't adhere to the oil?I think that it didn't adhere to the oil because, well...the food coloring is hydrophilic (Water loving) and it mixed with the water instead. (Yessssss, I know this one was short, please forgive me. ;)
Discuss the creation of the "lava". What do you think is happening?I think that the "lava" is created because the Alka Seltzer tablets react and oxidize the water making the food-colored water float through the oil making it look like a lava lamp.