chemistry Rate of reactions

1. RATE OF CHEMICAL
REACTIONS
By student :Mustafa Jamal

2. 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.

3. RATE OF REACTIONS
For example rate for these reactions
Iron rusting has a low reaction rate. This process is
slow.

4. RATE OF REACTIONS
Wood combustion has a high reaction rate. This
process is fast.

5. RATE OF REACTIONS
Nuclear explosion This process is very fast

6. 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.

7. 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.

8. RATE OF REACTIONS

9. 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.

10. RATE OF REACTIONS
concentration

11. 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
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12. 3:increased surface area of solid reactants
RATE OF REACTIONS

13. RATE OF REACTIONS

14. 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

15. Nickel is a catalyst in the production of margarine
(hydrogenation of vegetable oils).
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16. 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

17. Thank you for attention
RATE OF REACTIONS