Catalysts

[Ghadir Seder 1G]

What does it mean for a catalyst to "not be consumed during a reaction"?

[Jonathan Gong 2H]

A catalyst lowers the activation energy of a reaction but is not consumed. If you look at the elementary steps of a reaction, you will see that a catalyst is present as a reactant at the very beginning of a reaction, but is also produced as a product at the end. This means that is was not "consumed" in the reaction since it was not changed by the reaction.

[Samuel Tzeng 1B]

It means the catalyst is not consumed during the reaction

[Chris Tai 1B]

There are two types of catalysts that are both not necessarily consumed within the reaction. The first is a homogeneous catalyst, which is a same phase catalyst. This form of catalyst is made up of the same starting materials, and the reaction typically occurs within solution. The second is a heterogeneous catalyst, which is a different phase catalyst and catalysis typically occurs on a surface. In both examples, the catalyst isn't consumed by the reaction, but lowers the activation energy for the reaction to occur

[KnarGeghamyan1B]

It basically means the catalyst is not broken down into new molecules during the reaction.

[Lauren Stack 1C]

Catalysts are no consumed as they appear as an input, but also an output of a reaction. Thus, the amount of catalyst is not decreased by lowering the activation energy.