Question

What are the types of chemical reaction? Explain the four types of chemical reaction with example.

Answer 1

Hint: In a chemical reaction the substances on the left side of the reaction are converted into new substances present on the right side of the reaction. There are four basic types of chemical reaction namely Decomposition Reaction, Synthesis Reaction, Single-replacement Reaction and Double-replacement Reaction.

Complete Step By Step Solution:
The substances present on the left side of the chemical reaction are known as Reactants and the substances present on the right side of the chemical reaction are known as Products. The types of chemical reactions are-
Displacement Reaction: In this type of reaction the reactants decompose into two or more simpler substances. We can represent such type of reactions as- $AB\to A+B$, here the reactant AB is decomposing into two simpler products A and B. Example- decomposition of sodium chloride into sodium and chlorine,$NaCl\to Na +Cl$
Decomposition reactions are further classified into two types depending on the source which led to the decomposition of the reactants- 1) Thermal Decomposition Reaction (decomposition due to heat)
2) Photo Decomposition Reaction (decomposition due to light)
3) Electrolytic Decomposition Reaction (decomposition due to electricity)
Synthesis Reaction: This reaction occurs when synthesis of two different atoms or molecules takes place or we can say that in such reactions two different molecules or atoms interact with each other to form new molecules or products. This reaction is also known as Direct Reaction. Ex- synthesis of sodium and chlorine occurs to form sodium chloride.
$N{{a}_{2}}+C{{l}_{2}}\to 2NaCl$
Single-replacement Reaction: As the name clarifies, in such kinds of reactions one element is replaced or substituted for some other element in the reaction. The replacement of only one element takes place that’s why it is known as single-replacement or single displacement reaction.
Ex- $Zn+2HCl\to ZnC{{l}_{2}}+{{H}_{2}}$, here hydrogen in hydrogen chloride is replaced by zinc and it forms zinc chloride with it.
Double-replacement Reaction: In such reactions the doubly replacement of cations or anions exist in the ionic compounds.
Ex- $BaC{{l}_{2}}+MgS{{O}_{4}}\to BaS{{O}_{4}}+MgC{{l}_{2}}$ , here the chloride and sulfate anions are exchanged or replaced.

Note: There are other types of chemical reactions also like neutralization reactions and combustion reactions. In neutralization reactions acid and base neutralize each other to form salt and water as products. In a combustion reaction, the reaction of substance takes place with oxygen and energy is released in the form of heat and light. The products of such reactions are oxides.