The three changes of state during which energy is absorbed are:
1. Change from solid to liquid - Melting.
2. Change from liquid to gas - Vaporization
3. Change from solid to gas - Sublimation
All these changes of state require heat energy to break the attractive forces that hold the particles of the molecules together, so that they can move into more disorderly states. For instance, when heat is applied to a solid, the solid absorbs the heat and use it to break the attractive forces that are holding the molecules of the solid together. At a particular temperature, the attractive forces will be completely overcome and the solid framework will collapse, thus leading to the melting of the solid.
it’s somehow re-jiggered its
taste system so that the attractant that humans used to draw the insect to
poison bait—the sugar glucose—now tastes bitter to the roach, and they avoid it.
cockroaches began appearing that avoided the baits, and did so not because they
were averse to the poison, but because they were averse to the attractant, glucose. This new
trait turned out to be heritable, that is, it had a genetic basis.
If proven to be true, a hypothesis can become a theory, a theorem, or a law. Since her hypothesis is proven to be true, it is no longer a hypothesis.