Chemical reactions and equations

CHAPTER-1

CHEMICAL REACTIONS & EQUATIONS

Chemical reactions

1. Chemical reaction-

Chemical reactions are the processes in which new substances are formed.

Example-

Magnesium + oxygen----> Magnesium oxide

The burning of magnesium in air to form magnesium oxide is an example of chemical reaction.

Types of chemical reactions-

1. Combination reactions

2. Decomposition reactions

3. Displacement reactions

4. Double displacement reactions

5. Oxidation and reduction reactions

Components of chemical reaction are-

1. Reactant

2. Product

Characteristics of chemical reaction-

1. Evolution of gas

2. Formation of a precipitate (ppt)

3. Change in colour

4. Change in temperature

5. Change in state
Chemical equations

Chemical equation-

The method of representing a chemical reaction with the help of symbols and formulae of the substances involved in it is known as a chemical equation.

Example-

Mg₃N₂ + 3H₂O ----> 3MgO + 2NH₃

Some chemical equations are given below-

1) 2Fe₂O₃ +3C----> 4Fe+3CO₂

2)H₂SO₄+CaCO₃----> CaSO₄+H₂CO₃

3) 2H₂+0₂----> 2H₂O

4) CH₃COOH+C₂H₅OH----> CH₃COOC₂H₅+H₂O

5) 1 AgNO₃ + 1 LiOH ----> 1 AgOH + 1 LiNO₃

6) CH₄+2O₂----> CO₂+2H₂O.

7) Sn+2H₂SO₄----> SnSO₄+2H₂O+SO₂

8) CuO+H₂SO₄----> CuSO₄+H₂

9) Mg₃N₂ + 3H₂O ----> 3MgO + 2NH₃

10) N₂ + O₂----> 2 NO

Comments

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