The bubbles in your test tube

by Anne

Hey crew,

This just in from Karen K:

(to answer the question about how the bubbles that are attached to the DNA got there)

“At the interface the water and alcohol mix, and bonds are broken and reformed. Alcohol is bonding with water, more so than the percentage
initially. When this happens, heat is given off (this process has a name — “heat of mixing”). In this case the amount of heat is not sufficient for us to feel, but is enough to drive out some air that is dissolved in the water. This forms the bubbles, and since air is lighter than either water or alcohol, the bubbles can lift the DNA to the surface.”