Boron is less abundant element in Earth's crust as well as in cosmos too.
Residing on earth, its usual to talk about some elements present in vast quantities and others very rare. But unlike others, we have chosen Boron due to its exceptional relevance being less abundance in outer space too.
 |
| The abundances of the elements in the Universe |
Hydrogen alone forms about 74% of total mass of universe and other 24% is taken up by Helium. It means all the remaining elements are adjusted in mere 2% remaining.
Let us accept this fact for now. The above graph is logarithmic, so don't think that carbon or oxygen is anyway near to helium, keep that in mind. Now, focus on three elements after Helium, they are
Lithium, Beryllium & Boron. They are exceptional, being comparable to radioactive elements in their abundance.
In our studies, we repeatedly come through elements being more or less abundant. The usual reason we accept that, "Earth is just formed like that, who cares". It is true, but cosmic processes are also fairly responsible for what we got in our hand.
Here we would be seeing, the reasons for these 3 lighter elements of being less abundant cosmos-wide.
In short, it started from start, that is "The big bang"
The only two elements created in big bang were Hydrogen and Helium, there was Lithium too but in trace amount.
In the timeline, big bang happened about 13,800 million years ago. And it took 3,80,000 years to cool enough for atoms to exist !
Gas clouds containing Hydrogen got collected under influence of gravity to form stars(bigger). Inside a star fusion of hydrogen nuclei takes place to form Helium. Our 🌞 is also doing the same now. But after hydrogen is consumed, the sun will use helium to perform more fusions.
Problem starts here.
We have Hydrogen(A=1) and Helium(A=4) only by now.
- If we will fuse Hydrogen and Helium, we will get Lithium-5 which is unstable nuclei.
- If we will fuse Helium and Helium, we will get Beryllium-8 which is also unstable.
We are trapped. I am god, how will I form universe?
Here's the way, Beryllium-8 decomposes in 10^(-16) sec. That time is low, but long enough for Helium-4 to react with it to form Carbon-12.
Huh! Saved finally.
Now, it would continue with fusion to produce more elements. You can argue this way, we would only get even number elements. The fact is true, you can see the first chart, that zigzag line(even always remains up). Enjoy the beauty, leave reasoning. Odd elements are produced by beta decay of even number nuclides.
This fusion can continue up to Iron. After that it takes path of neutron capture to produce more higher elements. We would not go there in detail, as that isn't our issue.
We waited billions of years for other elements to form just because A=5 is unstable, otherwise there would be only heavier elements in this universe right from big bang itself. NATURE IS NOT IN HURRY.
We formed, everything except those 3 elements we wanted to. According to what i said till now, there shouldn't be existing any boron or beryllium, but we see them existing with our 👀.
How are they formed, then?
Shhh, there's a secret process known as X-process.
Cosmic rays are high energy particles(any) thrown out by large galactic bodies like supernova(blasting star). These particles travel with very high speed through the interstellar space. By chance, if a suitable particle in cosmic rays strikes the already available particles in space, a spallation (fission) happens to produce smaller particles. It could be Boron too.
And that's how it get produced.
Even more interesting is the importance of boron. Despite being rare, it has taken essential position in biology. Cell wall of plants require Boron. Also it is counted as an essential trace element for us humans.
This article is wholly based upon internet research and all the claims are based upon research at some time. But science changes, so things could be proven wrong at a later time.
References:
- https://www.forbes.com/sites/startswithabang/2019/11/14/this-is-why-three-of-the-lightest-elements-are-so-cosmically-rare
- https://www.scirp.org/journal/paperinformation.aspx?paperid=108122
- https://chem.libretexts.org/Courses/Saint_Marys_College_Notre_Dame_IN/CHEM_431:_Inorganic_Chemistry_(Haas)/CHEM_431_Readings/01:_Introduction_to_Inorganic_Chemistry/1.02:_The_Origin_of_Elements
- https://lovethenightsky.com/how-old-is-the-sun/
- http://hyperphysics.phy-astr.gsu.edu/hbase/Astro/mass5w.html
- https://imagine.gsfc.nasa.gov/educators/elements/imagine/07.html
- https://en.m.wikipedia.org/wiki/Boron
- https://en.m.wikipedia.org/wiki/Abundance_of_the_chemical_elements
- https://en.m.wikipedia.org/wiki/Oddo–Harkins_rule
- https://en.m.wikipedia.org/wiki/Cosmic_ray_spallation
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6073895
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4712861