What the residents lacked was activation energy. This is actually a term used by chemists to describe the minimum amount of energy required to initiate a chemical reaction, but it’s been adapted ...

Enzymes lower the activation energy necessary to transform a reactant into a product. On the left is a reaction that is not catalyzed by an enzyme (red), and on the right is one that is (green ...

Activation energy [Higher tier only] Activation energy is the minimum energy needed for ‘successful collisions’ where atoms within the reactants rearrange to form products.

The Activation Energy of the Initiating Process, Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Vol. 186, No. 1007 (Sep. 24, 1946), pp. 462-469 ...