Welcome to the eighth instalment of the Element of the Month – a regular feature on the Radleys blog.
As usual, we chose our element of the month by using a random number generator to produce a figure between 1 and 118 – the number of elements in the periodic table (so far!).
This month, boron (B), atomic number 5, was selected.
Boron – the Key Facts
The name “boron” reflects the similarity to its neighbour in the periodic table, carbon, and is also derived from its source mineral “borax” – but the origins of that word are still debated.
In contrast to carbon, boron is a low-abundance element. It is not naturally found on Earth in its pure form at all.
Boron is a metalloid – one of the few elements with properties between those of a metal and a non-metal. Another metalloid is germanium, which we’ve previously blogged about.
Fascinating Facts about Boron
We think one of the most interesting facts about boron is that it’s a key component of scientific glassware – okay, so we may be a little biased there!
Here at Radleys, we make glassware using borosilicate glass 3.3, which is 13% boron trioxide. Borosilicate glass is a special high quality form of glass that’s well known for its increased durability compared to normal glass, with great resistance to thermal shock as well as most chemicals, making it perfect for flasks and jacketed reaction vessels.
You can read more about it in our glass technical data sheet, available to download from our website. Amazingly, inert boron crystals show resistance to even hydrofluoric acid (HF), though it’s well known that HF can etch borosilicate glass.
And from chemistry to biology, boron may have been vital for the origin of life on Earth. How life first arose is still shrouded in mystery. The “RNA world” hypothesis theorises that RNA, which is a similar molecule to DNA but with enzymatic properties (catalysing reactions) and the ability to self-replicate in addition to simply storing information, was the beginning of life.
However, one of the building blocks of RNA – the sugar ribose – is unstable and naturally decomposes. This is where boron comes in – borates (oxidised boron compounds) can stabilise ribose, meaning they could have been vital for the formation of the first RNA.
The apparent lack of borate minerals on ancient Earth has led to the proposal that it came to Earth via Martian meteorites – although newer research indicates that there was more boron here naturally than first thought.
Like carbon, there are multiple allotropes of boron – different crystal and amorphous forms. This is another area of cutting edge research, with a new structure only quite recently revealed.
Boron has a history of being tricky to study – English chemist Sir Humphry Davy, who first isolated sodium, announced in 1808 that he had purified it, only for it to be proved that his product was actually a compound of 60% boron – not so pure after all. In fact, despite use of boron compounds for thousands of years – such as borax glazes in ancient China – “pure” boron (99%) wasn’t isolated until 1909, by American chemist Ezekiel Weintraub.
You might well have heard of “borax” before – this boron compound (sodium borate) can be found around the house, in products to clean laundry, wash hands, and even bleach teeth. Its antifungal and pesticide properties are put to use in other household products.
To boron! An element whose properties make it great for both children’s experiments and lab equipment for “big kids” – and that might have been pivotal for the emergence of life itself.
Join us next month, when we’ll be giving actinium the Element of the Month treatment.