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Imagine an acid that burns through almost any container you put it in. Spill some on your leg, and amputation is the only way to save your life.
That is hydrogen fluoride, an acid so powerful that chemists call it a super acid. It’s also known as the devil’s kimchi.
Acids are actually everywhere around us. Almost everything that’s mixed in water creates an acid or it’s opposite, a base.
[To understand how they both work and why hydrogen fluoride is satan’s preferred entree, we need to look at how water really works.
At it’s most basic, a glass of water is a glass of H2O molecules all jostling around together. But for chemists, it’s slightly more complicated.
Some H2O molecules in the glass break into two, being H and OH. Both of these have a charge, so they’re referred to as H+ and OH– ions. When this happens, the H+ rejoins another H2O molecule to form a H3O+ molecule. This is called ‘Arrhenius theory’.
Pure water has the perfect balance of H3O+ and OH– ions. They cancel each other out.]
It’s not just water. Other chemicals break apart as well.
If they break apart to give a H+ ion, it’s an acid.
[H+ ions….. what do they do.]
If they pull the ions from chemicals that wouldn’t otherwise give them up, it’s a base.
But if you dissolve some special types of chemicals into water, they will bring in more ions that tip the balance one way or the other.
If it adds H3O+, then the chemical is an acid. If it adds lots of them, it’s a strong acid.
If it adds OH–, then the chemical is a base. If it adds lots of them, it’s a strong base.
Both of these ions are highly reactive with other substances. For instance, if you pour a strong acid onto metal, the H3O+ ions chemically react with it, which turns it into gas and some residue.
The ions both exist as the balance for each other. You can’t have a substance that is both an acid and a base at the same time, because the H3O+ and OH– ions neutralise each other and just create water.
Because of this, we measure acids and bases on the same scale, called ‘potential of hydrogen’ or ‘pH’.
The pH scale. Image source: Anatomy & Physiology, 2014