Write two examples of: - 5 marks
a. Combination Reaction.
b. Decomposition Reaction.
c. Single Displacement Reaction.
d. Double Displacement Reaction.
e. Oxidation- Reduction Reaction.
Answers
Examples of Combustion Reaction
1 Burning of any kind of Wood or Coal to heat your home.
2 Car and buses burn petrol or diesel to run.
Example of decomposition reaction
1 The decomposition of carbonic acid in soft drinks, which can be represented by the chemical equation H2CO3 → H2O + CO2
2 The electrolysis of water to yield hydrogen and oxygen.
Example of double displacement reaction
1 The metals such as potassium, sodium, lithium, etc. react more vigorously with dilute acids forming metal salts and hydrogen gases.
2 Metals such as aluminium, zinc, magnesium, iron, etc., react safely with dilute acids.
example of double displacement reaction
When solution of barium chloride reacts with the solution of sodium sulphate, white precipitate of barium sulphate is formed along with sodium chloride.
BaCl2 + Na2SO4 ⇨ BaSO4 + 2NaCl
When sodium hydroxide (a base) reacts with hydrochloric acid, sodium chloride and water are formed.
NaOH + HCl ⇨ NaCl + H2O
example of oxidation and reduction
1) Cuo+H2(g)---> Cu+ H20 (I) Cuo is reduced to Cu H2 is oxidised to H20 Cuo is the oxidising agent H2 is the reducing agent
2) H2S + Cl2 ----> S+2HCI H2S is oxidised to S Cl2 is reduced to HCI Cl2 is the oxidising agent H2S is the reducing agent The substance which gets oxidised is