(from wikipedia) Fractional distillation is the separation of a mixture into its component parts, or fractions, such as in separating chemical compounds by their boiling point by heating them to a temperature at which several fractions of the compound will evaporate. It is a special type of distillation. Generally the component parts boil at less than 25 °C from each other under a pressure of one atmosphere (atm). If the difference in boiling points is greater than 25 °C, a simple distillation is used.
video from BBC documentary Absolute Zero and explanation from wikipedia
Superfluidity is a state of matter in which the matter behaves like a fluid without viscosity and with infinite thermal conductivity. The substance, which looks like a liquid, will flow uncontrollably, and also will be at exactly the same temperature throughout itself. Despite its lack of viscosity, the liquid still has surface tension which allows it to rise up the sides of its container without the normal restrictions of flow. This allows the liquid to "flow" up the sides of the container and over the top.
Ammonium dichromate (NH4)2Cr2O7 decomposes when heated yielding green chromium(III) oxide, nitrogen and water vapor. It is a comproportionation reaction where Cr(+6) of Cr2O72- gets reduced to Cr(+3) of Cr2O3 oxidising N(-3) of NH4+ to N(0) of N2 gas. This process needs quite a lot of energy to get started and it can be used to simulate a chemical volcano. However, if hot (NH4)2Cr2O7 is put in contact with NH3(g) (ammonia), obtained from a saturated NH4OH solution, the comproportionation is much faster as it can be seen on this video...
from wikipedia A Rube Goldberg machine, device, or apparatus is a deliberately over-engineered machine that performs a very simple task in a very complex fashion, usually including a chain reaction. The expression is named after American cartoonist and inventor Rube Goldberg.
This music video, by the American band OK GO very nicely illustrates the principles of a Rube Goldberg machine....
