Displacement reaction

A chemical reaction is when one or more substances which are reactants are changes into one or more different substances which then becomes the product. A chemical reaction is written with the formula of reactants on the left side, and formula of the products formed on the right. An arrow is placed in-between the reactants and the products. They are 5 types of chemical reaction;

1. Synthesis reaction/combination
2. Decomposition Reaction
3. Displacement or Replacement Reaction
4. Acid Base Reactions
5. Combustion Reaction

I'll be explaining one of these five reaction which will be Single displacement reaction. Single displacement reaction is part of the reaction "Displacement or Replacement Reaction.

Single displacement reaction happen when a cation(positive) and an anion(negative) swap from a compound. 

The general formula for a single replacement reaction is

$\text{A + B-C → B + A-C}$

where $\text{A}$ is an element and where $\text{B-C}$ is a compound.

The reaction produces a new element $\text{B}$ and a new compound $\text{A-C}$.

→

Example

Zn + H₂SO₄ → ZnSO₄ + H₂

This example show how zinc take hydrogen's place from hydrogen sulphate or sulfuric acid, to form zinc sulfate. Since only cation is exchanged here, this is a single displacement reaction. 

A Single displacement reaction is exothermic. An exothermic reaction means that energy is released by heat or light. This reaction is exothermic because;

 In the reaction 

$\text{A + B-C → B + A-C}$, we must break the $\text{B-C}$ bond and form an $\text{A-C}$ bond.

If formation of the $\text{A-C}$ bond releases more energy than it took to break the $\text{B-C}$bond, there will be a net release of energy. 

These reaction affect our daily lives, even when we don't know it is. For example, when we are very cold we turn on the heater or light a fire. In this case, the heater and the fire react as exothermic reaction and keeps us warm. 

Video to watch: https://www.youtube.com/watch?v=qhmTXdOKTBo 

Video: https://www.youtube.com/watch?v=eJXL0IrbtqE

Videos will help you understand better what my blog is about.

Citations:

“Exothermic Reaction.” Wikipedia, Wikimedia Foundation, 17 Sept. 2018, en.wikipedia.org/wiki/Exothermic_reaction. (Paragraph 1)

“Single Replacement Reactions.” Khan Academy, Khan Academy, www.khanacademy.org/science/chemistry/chemical-reactions-stoichiome/types-of-chemical-reactions/a/single-replacement-reactions. ( Example)