A Catalyst?
A catalyst is a substance which changes the rate of a chemical reaction
(usually speeding it up), but when the reaction is finished, the
catalyst is chemically the same as it was at the beginning. This means
that none of it is used up in the reaction.
Catalysts are quite substrate-specific, which means that they are only good at changing the rate of one type of chemical reaction and not much good with any others. Some reactions don't have any catalyst to speed them up, but they are usually affected by temperature, concentration or the size of solid lumps (if the reaction has a solid present!). For this reason, it is wrong to say that heat (or temperature) is a catalyst - don't make this common mistake!
Catalysts are very important in industry, where it would be uneconomic (or even impossible) to carry out certain chemical reactions. Examples of industrial processes which use catalysts are:
When a catalyst is doing its job in a living thing, we call this kind of catalyst an Enzyme. So a biological (in a living thing) catalyst is an enzyme.
If it were not for the enzymes in our bodies, almost all of the important chemical reactions which are needed to keep us going would be too slow and we would die.
Catalysts are quite substrate-specific, which means that they are only good at changing the rate of one type of chemical reaction and not much good with any others. Some reactions don't have any catalyst to speed them up, but they are usually affected by temperature, concentration or the size of solid lumps (if the reaction has a solid present!). For this reason, it is wrong to say that heat (or temperature) is a catalyst - don't make this common mistake!
Catalysts are very important in industry, where it would be uneconomic (or even impossible) to carry out certain chemical reactions. Examples of industrial processes which use catalysts are:
- Making margarine from vegetable oils (Nickel catalyst)
- Making sulphuric acid (Vanadium catalyst)
- Making ammonia (Iron catalyst)
- Making nitric acid (Platinum catalyst)
- Making sulphur dioxide (Platinum catalyst)
- Making polymers (plastics) (Titanium catalyst)
When a catalyst is doing its job in a living thing, we call this kind of catalyst an Enzyme. So a biological (in a living thing) catalyst is an enzyme.
If it were not for the enzymes in our bodies, almost all of the important chemical reactions which are needed to keep us going would be too slow and we would die.