1. Popular equations in chemistry
1) Decomposition of hydrogen
peroxide in the presence of catalyst
2H2
O2
 2H2
O + O2

2. Popular equations in chemistry
2) Reaction of sodium thiosulphate
with sulphuric acid
Na2
S2
O3
+ H2
SO4

Na2
SO4
+ H2
O + S + SO2

3. Popular equations in chemistry
3) Reaction of marble chips with
sulphuric acid
CaCO3
+ H2
SO4

Ca SO4
+ H2
O + CO2

4. Popular equations in chemistry
4) Reaction of ethanol with propanoic
acid
C2H5OH + C2H5COOH 
C2H5COOC2H5+ H2O

5. Popular equations in chemistry
5) Contact Process – 4 stagesi) S + O2
 SO2
ii) 2SO2
+O2
 2SO3
iii) SO3
+ H2
SO4
 H2
S2
O7
iv)
H2
S2
O7
+H2
O  2H2
SO4

6. Popular equations in chemistry
6) Haber Process –
N2
+3H2
 2NH3

7. Popular equations in chemistry
7) Heating of zinc carbonate
ZnCO3
 ZnO + CO2
8) Combustion of ethanol
C2H5OH + 3O2
 3H2O + 2CO2

8. Popular equations in chemistry
9) Displacement of copper by zinc
Zn + CuSO4
 Cu + ZnSO4
10) Sulphuric acid and barium hydroxide
H2SO4 + Ba(OH)2

BaSO4 + H2O

9. Place hydrogen and
carbon in electro
chemical series and
reactivity series
• K
• Na
• Ca
• Mg
• Al
• Zn
• Fe
• Sn
• Cu
• Ag

10. • K
• Na
• Ca
• Mg
• Al
• Zn
• Fe
• Sn
• Cu
• Ag
electro
chemical
series
reactivity
series
--H
H---
--C

11. Popular equations in chemistry
11) Reaction of magnesium in carbon
dioxide gas
Mg + CO2
 MgO + C
12) lead(II) oxide and hydrogen gas
PbO + H2
 Pb + H2O

12. Popular equations in chemistry
13) Reaction of magnesium oxide with
carbon
MgO + C  no reaction
14) copper(II) oxide and carbon
CuO + C  CO2
+ Cu

13. Popular equations in chemistry
15) Reaction of copper(II) oxide with
magnesium
Mg + CuO  Cu + MgO
16) Copper and magnesium oxide?
Cu + MgO  no reaction