How does temperatyre affect the rate of reaction?

Answer 1

Enzymes are biological catalysts. They speed up

metabolic reactions in the body but remain chemically unchanged

themselves. Enzymes contain an active site. This is a region to which another molecule may bind. This molecule is known as the substrate, and is usually specific to the active site of the particular enzyme, which breaks it down. Substrates

will not usually fit into any other active sites other than that of

the enzyme it is specified to. This can be explained as a lock and key

model, where the lock and key are specific to each other, only, that

there are many of the same kinds of lock and key when it come to the

enzymes. The higher the temperature, the higher the rate of

reaction up to a certain point. This is due to the fact that the

particles gain kinetic energy and subsequently move around more

vigorously. Thus, the chance of there being a successful collision

between the enzyme and substrate molecule increases as reacting

particles with collide more frequently with increased kinetic energy. Enzymes have a very specific three-dimensional shape, held together by

ionic and hydrogen bonds. If the amino acids are too vigorous in their

motion, then, these bonds will brake. Once the bonds have been broken,

the enzyme is said to have become denatured. As a result of becoming

denatured, the enzymes' rate of activity becomes less because the

enzyme loses its specific three-dimensional shape. The enzyme will

start to become denatured after around 40ºC as enzyme activity is

usually at its optimum at this temperature. After this, the rate of

reaction will probably deteriorate. After 60ºC, there is likely to be

no reaction, as the enzymes would probably be completely denatured by

then.

Answer 2

Generally, an increase in temperature will increase the rate of a chemical reaction by providing more kinetic energy to the molecules involved, leading to more frequent and energetic collisions. Conversely, decreasing temperature will slow down the rate of reaction due to less energy available for collisions. However, extreme temperatures can denature enzymes and hinder the reaction.