XII Chemistry BIEK Topic - Fertilizers (Short Note)

Fertilizers (Short Note)
Definition
Fertilizers are the water soluble substances which provide one or nutrient materials to the soil essential for the nourishment of plants.




Explanation
Fertilizers are water-soluble salts that are absorbed by the plants through osmosis process. Fertilizers are mostly inorganic salts containing nitrogen phosphorus or potassium etc. these elements are essential for the growth and development of plants. Those nutrient materials which plant needs in large quantities are called Macro Nutrients. Those nutrient elements which plant need in small quantities are called Micro Nutrients.




Functions of Fertilizers
The main functions of fertilizers are

1. It helps the soil to make up the deficiency of nutrient element and becomes fertile again.

2. The main function of fertilizers is to maintain the pH of soil to neutrality (7 - 8) or slightly alkalinity (10).




Types of Fertilizers
Fertilizers have been classified into the following types.

1. Natural Fertilizers

2. Artificial Fertilizers


1. Natural Fertilizers

Natural Fertilizers are also known as organic fertilizers. The main source of natural fertilizers is the excretory product of animals and decade product of plants.


2. Artificial Fertilizers

Artificial Fertilizers are also known as synthetic fertilizers and mineral fertilizers. They are obtained from raw mineral materials.

Artificial fertilizers have been further classified into

a. Nitrogenous Fertilizer

In these fertilizers, nitrogen is present as the essential element.


Example

Ammonium Nitrate - NH4NO3

Ammonium Sulphate - (NH4)2SO4


b. Potassic Fertilizer

In these fertilizers, Potassium is present as the essential element.


Example

Chilli Salt Peter - KNO3


c. Phosphatic Fertilizer

In these fertilizers, phosphate is present as the essential element. Phosphatic fertilizers are further classified into following.


i. Super Phosphate

The raw material of super phosphate fertilizer is phosphorite. The molecular formula of Phosphorite is [Ca3(PO4)2]3 CaF2. This rock reacts with sulphuric acid and converts into water soluble super phosphate.

Ca3(PO4)2 + 2H2SO4 ----> Ca(H2PO4)2 + 2CaSO4

The mixture of calsium dihydrogen phosphate and gypsum is called super phosphate.


ii. Triple Phosphate

This phosphate fertilizer is obtained by the decomposition of phosphate rock or phosphorite with phosphoric acid.

Ca3(PO4)2 + 4H3PO4 ----> 3Ca(H2PO4)2