The Chemistry of/in things

By Filipe Monteiro Silva, Research Assistant at the Centre for Applied Photonics.

Let’s think about the year 2020.

A year that, according to many, seemed to be promising, but quickly became one of the most hectic and noteworthy years, for the wrong reasons; let’s see:

Ebola, yellow and dengue fevers, ruthless fires in Australia, Black Lives Matter, plane crashes, explosions in Lagos and Beirut, clashes in Azerbaijan, earthquakes, usurpation of power in Belarus, knife and gun attacks in multiple European countries, minks with SARS-CoV-2, Trump, a hint of civil war in the U.S.A. and, finally (yet, far from over), COVID-19.

And for these reasons, I will not address any of the aforementioned subjects! Better yet: I will only resort to one of them as a segue.

I have been working at INESC TEC since 2014, and I am a Chemist. I came to this institution to help improve some of the techniques adopted here – while improving myself, as I worked and contributed to some projects. Please keep in mind that I wrote Chemist with capital “C” for two reasons[1]: because I’m very proud of my profession, and because it’s important to make a distinction between Chemist and “chemical”, a term that we so often hear people saying. Probably due to the increasingly “frequent” use of the Anglo-Saxon term meaning chemical compounds, substances or reagents. It’s the word one should use to identify the chemical substances that make up everything; the table we have in our kitchen, that medicine to treat headaches, the components of our mobile phones or the “fuel” that nurtures us and helps us moving around.

Everything consists of small clusters of Lego®-type pieces – the molecules -, which are made up of smaller elements – the atoms. These basic units of matter are very similar to a small planet: think of a planet with a few moons circling its orbit. The nucleus (a cluster of protons and neutrons) is actually the planet, and the electrons, orbiting unremittingly, are the moons. One could think that things would end there; but they don’t: atoms are composed of even smaller elements, which we still don’t truly understand (quarks, gluons, etc.).

In August 2020, something unlikely happened in Beirut (Lebanon): almost 3000 T of ammonium nitrate (NH₄NO₃) combusted rapidly, leading to an exothermic reaction, and an inexorable devastation within a radius of hundreds of meters. When interviewed by Jornal 2, Professor António Fernando Silva (a person who deeply influenced my academic and personal path) explained, in a very direct way, what this chemical compound actually is: “it is a simple type of salt, soluble – quite soluble, actually – in water, used as a fertiliser, and as component of explosives. It is white, and it looks harmless. The problem with ammonium nitrate is the fact that it can cause an explosion, particularly when stored in large quantities and subject to an increase in temperature or internal pressure”.

Like the majority of chemical compounds, this one has an existential duality: one can use it for good or bad reasons. Ammonium nitrate is extremely useful for fertilising purposes, enabling the smart development of crops, sources of food (“fuel”). However, when observing its properties as a solid compound, anyone with a trained way can realise that, under certain conditions, it does more than fertilise.

This duality is not exclusive to this chemical substance: nitro-glycerine is a famous explosive; however, in the right amount, it can be used as a medicine – namely, as a powerful vasodilator – that has already saved many lives. There is a quote by Paracelsus that proves my point, and validates the previous example: “The dosage makes it either a poison or a remedy”.

There are no bad chemical compounds, only bad ways to handle them. Depending on how people use them, the result could be either good or bad. “Chemical” things are not necessarily (or at all) bad, and not all things “natural” are essentially good. This is a common misconception: atoms and molecules are the elements that make up everything. A synthesised X molecule is the same as the X molecule obtained, for instance, in nature. Any argument claiming the opposite is fundamentally untrue. Professor Carlos Corrêa once presented a remarkable and very simple example, in his final class:

“People have a negative outlook on Chemistry, perhaps because they are easily influenced. A group of people was asked about their notion, according to what was presented to them. In the first example, researchers presented the term E300, used in the labelling of food products. The general reaction was of concern, because ‘things with acronyms are artificial and clearly harmful’. It was followed by Ascorbic Acid, and the reaction was panic, because ‘everyone knows that an acid corrodes, burns and kills’. Finally, researchers mentioned Vitamin C, and the general reaction was one of coolness and assurance, because ‘vitamins are good’. What people didn’t know is that these are three different designations for the same chemical compound…”

In short, not all things “natural” are fundamentally good, while “artificial” things are not necessarily bad.

If we consider that Lavoisier was right and that “nothing is lost, nothing is created, everything is transformed”, it’s safe to say that the molecules that are part of me, were once dust from the stars, dirt that other beings stepped on, or even the air that dinosaurs breathed.

So, my molecules are the same as those of my neighbour, my friend, and those of anyone else who lives in this world; the only difference is that they were arranged in a slightly different way. Wait… does that mean that we are all made of the same material, and that we are all equal (even if different)?

TL; DR: Chemists are people with a background in Chemistry; chemical substances or compounds are things; artificial things are not necessarily bad, while natural things are not essentially good; we’re all the same.

[1] TN: “Químico” in Portuguese, is commonly and wrongly used by Portuguese-native speakers to refer to both the Chemist and the chemical products, most probably due to the use of the Anglo-Saxon term “chemical”, that roughly translates into “químico”.