6 ms·

Layperson here. It’s my understanding that energy can neither created not destroyed. So if a reaction needs more energy otherwise, then how do catalysts provide

• ace2358 5y ago
  I don’t think they provide the energy, they change the required energy for a reaction to occur. My understanding is that is can happen due to the physical structure of the catalyst changing the electronic configuration of the molecules being reacted. I think often instead of the two molecules coming into contact and reacting, the two molecules and the catalyst come into contact. It’s a whole different reaction, but the catalyst molecule doesn’t change its composition and is left unchanged after the reaction. I guess maybe a terrible analogy would be you’re trying to cross a flat field but there is a large group of animals, say, cows in the way. You’d never be able to get through the crowd of cows without exerting a lot of energy. Then suddenly a dog, catalyst, come over and starts shooing off the cows. Now the cows have moved out of the way and the flat field is clear. You can now make the journey while expending less energy. Hmm maybe someone else can explain it better!
• infogulch 5y ago
  You can think of the energy of the reactants and products as valleys separated by a mountain. The "normal" reaction requires the reactants in their base energy state (the bottom of the valley) to climb up the whole mountain, thus it will be very slow. The "just add enough heat" method is like flooding the whole mountain range up to the peak -- it technically works but causes other issues. Adding a catalyst is like digging a tunnel through the mountain.