How does a catalyst function?

Answer 1

In chemistry, they can work by adsorption (although there are other methods). This is when the catalyst attaches itself to the reactant particles and then weakens the bond between them, making it easier to react, thus 'lowering the activation energy' (the energy required for a reaction to start).

Answer 2

A catalyst is a substance that affects the speed of a chemical reaction, but is itself unchanged at the end of the reaction. An example of this is the enzyme, where it is a biological catalyst that speeds up a reaction but does not take part in it, and is unchanged at the end of the reaction. A literal example would be a spade, where the spade is the "catalyst" digging into the ground. after the "reaction", the spade is remains unchanged.

Answer 3

A catalyst is something that provides an alternative route for a reaction to occur, either by allowing the reaction to occur at a different transition state or by changing the activation energy, and the catalyst itself does not undergo any chemical change during the reaction (materials that do undergo chemical changes are not classified as catalysts, and it gets murkier when you ask about physical changes, i believe there is an iron based material that acts like a catalyst but undergoes a physical change)
Alternatively, catalyst can mean an event or a person that produces progress (whether positive or negative), e.g. when someone says 'his appointment was the catalyst for the company's success)

Answer 4

decreasing the activation energy required for a reaction