How Does Catalysts | Chemistry | Khan Academy Work?

A catalyst is like a helper who makes a job go faster, without changing the final result.

Imagine you and your friend are trying to build a big tower with blocks. It takes a while because you have to stack each block one by one. Now, imagine a super-fast robot comes in to help you both, it grabs blocks quickly and places them where they need to be. The tower still looks the same in the end, but it gets built much faster. That’s what a catalyst does in chemistry.

In a chemical reaction, molecules are like puzzle pieces that need to fit together to make new things. Sometimes they have trouble finding each other or joining up, kind of like when you’re trying to find your friend in a crowd.

A catalyst is like a signpost or a path that helps these molecules find each other easier. It doesn’t get used up in the reaction, so it can help again and again, just like how your robot helper could build many towers without getting tired. A catalyst is like a helper who makes a job go faster, without changing the final result.

Imagine you and your friend are trying to build a big tower with blocks. It takes a while because you have to stack each block one by one. Now, imagine a super-fast robot comes in to help you both, it grabs blocks quickly and places them where they need to be. The tower still looks the same in the end, but it gets built much faster. That’s what a catalyst does in chemistry.