Chemical reaction:
It is a process that involves breaking the
existing bonds in the reactant molecules and
forms new bonds in the products.
 Importance of chemical reactions:
1. Burning of car fuel in the car engine.
2. Plants make their food through
photosynthesis process.
3. Medicine, fertilizers, artificial fibers are
examples of outcomes of some chemical
reactions.

1
1.
2.
3.
Thermal decomposition reactions.
Substitution reactions.
Oxidation reduction reactions.
2

3
2 HgO
2Hg + O
2
4
Cu(OH)2
CuO
blue
black
+ H 2O
5
CuCO3
Green
CuO +CO2
black
6
CuSO4
blue
CuO + SO3
black
7
2NaNO3
2 NaNO2 + O2
8
 Air
bags:
They are considered one of the most
important safety means in cars at
emergencies.
9
10
They are the reactions which depend
on the activity of the metals , where
the element which is more active
substitutes (replaces) the less active
one in its compounds.
 The activity of metals can be
determined by using the
“chemical activity series”

11
 It
is the arrangement of the
metals in an descending order
according to their chemical
activity .
12
13
1.Simple substitution reactions
2. Double substitution reactions
14
+
+
Types of simple substitution reactions
A. Metal substitutes Hydrogen of acid or
water.
B. Metal substitutes another metal in its salt
solution.
15
2Na +2 H2O
2NaOH + H2
16

Zn + 2HCl
ZnCl2 +H2
17

2Al + 6HCl
2AlCl3 +3H2
18

Mg + CuSO4
MgSO4 +Cu
19
 booklet
page 13
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+
21

1. Reaction between acid and alkali

3. Reaction between two salt solution.
( Neutralization reaction)
 2. Reaction between acid and salt.
22

Acid + Alkali
Salt + Water

HCl
NaCl + H2O
+ NaOH
23
NaCO3 + 2HCl
2NaCl + H2O+CO2
3. Reaction between two salt
solution.
NaCl +AgNO3
NaNO3 +AgCL
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