When you think of chemical reactions, you might think of them as irreversible, permanently changing one substance into another. While this is true in some cases, some chemical reactions are reversible, and we can take the products of the reaction and turn them back into the reactants. These reversible reactions can, under certain conditions, reach what we call ‘equilibrium’. Equilibrium can be a tricky concept to understand, but this graphic tries to make it a little clearer.
Even if you’re not a chemist, you’ll doubtless remember learning about acids back in school. They’re routinely described as strong or weak, concentrated or dilute. But what’s the difference between a strong acid and a concentrated acid? Explaining that is a little trickier than it sounds; in this graphic, we give it a go!
One for the chemistry students (and teachers!) out there today, with a look at how we can work out the shapes of some simple molecules using Valence Shell Electron Pair Repulsion (VSEPR) theory. These shapes are decided by the arrangement of electrons around the central atom in the molecule.