Li speed dating
The bomb set off a massive pressure cave that would have crushed the life out of any fighters hiding in the cave, and it sent a mushroom-like cloud into the sky, Martin reports.Scientists have understood for some time that the most abundant elements in the Universe are simple gases like hydrogen and helium.These make up the vast majority of its observable mass, dwarfing all the heavier elements combined (and by a wide margin).And between the two, helium is the second lightest and second most abundant element, being present in about 24% of observable Universe’s elemental mass.Helium was one of the first elements to be found to have superfluidity. Today, helium gas is used in a wide range of industrial, commercial and recreational applications.In 1938, Russian physicist Pyotr Leonidovich Kapitsa discovered that helium-4 has almost no viscosity at temperatures near absolute zero (superfluidity). The most well-known is perhaps flight, where helium gas (being lighter than air) naturally provides buoyancy for airships and balloons.The greatest use is in cryogenic applications, where liquid-helium acts as a coolant for superconducting magnets in MRI scanners and spectrometers.
Owing to its unique properties – which include a low boiling point, low density, low solubility, high thermal conductivity and inertness – helium is used for a wide range of scientific and medical applications.
The nucleus of the helium-4 atom is identical with an alpha particle, two bound protons and neutrons that are produced in the process of alpha decay (where an element decays, releasing mass and becoming something else).
The inertness of helium is due to the stability and low energy of it’s electron cloud state, where all of its electrons fully occupy 1s orbitals in pairs, none possessing angular momentum and each cancels the other’s intrinsic spin.
However, in 1882, Italian physicist Luigi Palmieri detected helium on Earth when analyzing lava from Mount Vesuvius after it erupted in that year.
And in 1895, while searching for argon, Scottish chemist Sir William Ramsay managed to isolate helium by treating a sample of cleveite with mineral acids.