In stars like the Sun, carbon is the end, and the only way heavier elements are formed is by the production of neutrons, which can bump you up the periodic table very slowly. Once helium fusion has fully run its course, the star's outer layers will be expelled in a planetary nebula while the core shrinks down to form a white dwarf. Planetary nebulae take a wide variety of shapes and orientations depending on the properties of the Supergiant stars and giant stars entering the planetary nebula phase are both shown to build up many important elements of the periodic table via the s-process.
But there are stars much more massive than this, capable of undergoing carbon fusion as the core contracts down even farther. Stars where this occurs will fuse carbon into oxygen, oxygen into neon, neon into magnesium, and up and up until they've created silicon, sulphur, argon, calcium, and elements all the way up to iron, nickel and cobalt.
When they've finally run out of useful fuel, they'll end their lives in a cataclysmic event known as a supernova. These supernovae are responsible for a large fraction of many of the Universe's heavier elements, while other events like white dwarf-white dwarf mergers or neutron star-neutron star mergers produce the remainder. Between stars that end their lives in planetary nebulae or supernovae, as well as the mergers of their remnants, we can account for the overwhelming majority of the elements found in nature.
The anatomy of a very massive star throughout its life, culminating in a Type II Supernova when the The final stage of fusion is typically silicon-burning, producing iron and iron-like elements in the core for only a brief while before a supernova ensues. Many of the supernova remnants will lead to the formation of neutron stars, which can produce the greatest abundances of the heaviest elements of all.
There are a couple of unstable elements that get skipped — technetium and promethium — because they decay away too quickly. But three of the lightest elements need a new method, because none of these mechanisms create beryllium or boron, and the amount of lithium we see cannot be explained by the Big Bang alone. The elements of the periodic table, and where they originate, are detailed in this image above.
Hydrogen fuses into helium, and helium is element 2. It takes three helium nuclei to fuse together into carbon, where carbon is element 6. But what about those three elements in between? What about lithium, beryllium, and boron? As it turns out, there are no stellar processes that make these elements in sufficient quantities without destroying them almost as quickly, and there's a good physics reason why.
If you were to add hydrogen to helium, you'd create lithium-5, which is unstable and decays almost immediately. You could try to fuse two helium-4 nuclei together to make beryllium-8, which is also unstable and decays almost immediately.
In fact, all nuclei with masses of either 5 or 8 are unstable. With 8 million tons, Chile has the world's largest known lithium reserves. This puts the South American country ahead of Australia 2. Within Europe, Portugal has smaller quantities of the valuable raw material. In general, heavier elements are rare and light elements are abundant, but there are three big exceptions: lithium, beryllium, and boron. If we could create the heavy elements found on planet Earth, the Universe could have been ready for life from the time the first stars were born.
Chances are you have seen it. The hardest pure element is carbon in the form of a diamond. Diamond is not the hardest substance known to man. Some ceramics are harder, but they consist of multiple elements. A team of researchers using the ISOLDE nuclear-physics facility at CERN has measured for the first time the so-called electron affinity of the chemical element astatine , the rarest naturally occurring element on Earth. The most expensive natural element is francium.
Although francium occurs naturally, it decays so quickly that it cannot be collected for use. Only a few atoms of francium have been produced commercially, so if you wanted to produce grams of francium, you could expect to pay a few billion U.
The atomic weight of helium is 4. The French astronomer Pierre Janssen discovered helium in the spectrum of the corona of the sun during an eclipse in Helium is the second most abundant element in the universe, after hydrogen. Lithium is a highly reactive element, particularly so with water.
It can be toxic except when given in tiny amounts. Lithium does have several uses, though, most importantly as a key part of lithium-ion batteries. Compounds containing lithium, including lithium oxide, lithium chloride, lithium stearate and lithium carbonate are used in a wide range of applications, from the production of glass and ceramic to pharmaceuticals. Lithium is formed in stars and some was also formed in the early stages of the universe, around the time of the big bang.
Beryllium is the fourth-lightest element, with four protons, five neutrons and four electrons, and the chemical symbol Be. Beryllium and compounds containing it are dangerous to humans, with toxic and carcinogenic effects, but it does have practical uses in industry. There are many other uses for beryllium too, including in x-ray lithography and in nuclear reactors.
Beryllium is formed in stars, and trace amounts were created in the aftermath of the big bang. Lee Johnson is a freelance writer and science enthusiast, with a passion for distilling complex concepts into simple, digestible language.
So it would float on water if it were not too busy reacting with it, like but not as violently as the related elements sodium and potassium. Tim Green, Bradford, Yorkshire The reason is that lithium is much too reactive and has too low a melting point to be much use in hydraulic engineering.
A violent reaction takes place on contact between Lithium and water. The heat of reaction is enough to melt the lithium metal and ignite the hydrogen gas that is produced by the reaction. The result is a flaming globule of liquid metal scooting around on the surface. When I was at school this was a favourite demonstration during chemistry classes, but we were less safety conscious in those days. Martin Thomas, Farnham, England Carbon also has a lower atomic number than Oxygen, but like Lithium exists as a solid, and is much more dense than Oxygen.
Floatation occurs because of buoyancy - the difference in density between two objects. This is why Archimedes jumped out of the bath, and is the reason why steel ships can float on water.
However it is soft, reacts with oxygen and water and is somewhat toxic. It melts at a relatively low temperature. Not a meterial to build a ship. The next is Beryllium which is physically very good but a deadly poison. Next, Sodium - more reactive than Lithium.
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