Question

For a given chemical reaction, the addition of a catalyst provides a different reaction pathway that does what?

Answer 1

Lowers the energy of activation required to get you to the transition state.

Explanation:

Catalysts simply help to lower the activation energy. This is the energy that you need to overcome to get the ball rolling to products. Think miniature golf - hitting the ball over a ridge. The energy of activation is getting the balls to the top of that ridge - a catalyst is like drilling a hole through the ridge so the ball has to rise less high.

For a basic example - at any given temperature, you have a small population of reactants that have enough energy to overcome this barrier and react. But not a large population. Imagine like crickets trying to jump out of a bathtub. One, maybe 2 can do it, but most can't.

Now if you heat the reaction up, more of the molecules have more energy and you have a larger population of molecules that have enough energy to react. For the crickets, this might be like adding a cricket-eating monster and scaring them - some will find a bit more ability to jump and get out!

Now a catalyst, this just lowers the activation energy, or the energy those reactants need to achieve to react...so at a given temperature, in the presence of a catalyst, you have more population that can react. For the crickets, it is like drilling a hole in the side of the bathtub half way up. Before, you only had 1 or 2 that could jump out, but now you've got a lot more than can make the jump.

Hope that helps.