RATE OF CHEMICAL

REACTIONS

By student :Mustafa Jamal

RATE OF REACTIONS

What does rate of reaction mean?

The speed of different chemical reactions varies

hugely. Some reactions are very fast and others are

very slow.

The speed of a reaction is called the rate of the

reaction

On :The rate of a reaction depends

the frequency of collisions between particle

the energy with which particles collide.

RATE OF REACTIONS

For example rate for these reactions

Iron rusting has a low reaction rate. This process is

slow.

RATE OF REACTIONS

Wood combustion has a high reaction rate. This

process is fast.

RATE OF REACTIONS

Nuclear explosion This process is very fast

RATE OF REACTIONS

factors affect the rate of reactions

1: increased temperature

2: increased concentration of dissolved

reactants,and increased pressure of

gaseous reactants

3:increased surface area of solid reactants

4: use of a catalyst.

RATE OF REACTIONS

1 : Temperature

A : When you raise the temperature of a system, the

molecules bounce around a lot more.

They have more energy. When they bounce around

more, they are more likely to collide.

That fact means they are also more likely to

combine.

B :When you lower the temperature, the molecules

are slower and collide less. That temperature drop

lowers the rate of the reaction.

RATE OF REACTIONS

RATE OF REACTIONS

2: concentration

If there is more of a substance in a system,

there is a greater chance that molecules will

collide and speed up the rate of the reaction.

If there is less of something, there will be

fewer collisions and the reaction will probably

happen at a slower speed.

RATE OF REACTIONS

concentration

Pressure affects the rate of reaction,

especially when you look at gases. The gas

particles become closer together, increasing

the frequency of collisions. This means that

the particles are more likely to react.

lower pressure higher pressure

RATE OF REACTIONS

3:increased surface area of solid reactants

RATE OF REACTIONS

RATE OF REACTIONS

4: use of a catalyst.

A catalyst is a substance which speeds up a reaction, but is

chemically unchanged at its end. When the reaction has

finished, the mass of

catalyst is the same as at the beginning..

Many catalysts are transition metals or their compounds. For

example:

Iron is a catalyst in the production of ammonia from nitrogen

and hydrogen (the Haber process).

RATE OF REACTIONS

Nickel is a catalyst in the production of margarine

(hydrogenation of vegetable oils).

RATE OF REACTIONS

catalysts

Why are catalysts so important for industry?

Products can be made more quickly, saving

time and money.

Catalysts reduce the need for high

temperatures, saving fuel and reducing

pollution.

Catalysts are also essential for living cells.

Biological catalysts are special types of protein

called enzymes.

RATE OF REACTIONS

Thank you for attention

RATE OF REACTIONS