Which one of the following nutrients is not available in fertilisers?

Options

A. Nitrogen
B. Phoshorus
C. Iron
D. Potassium

Answer

C

Explanation

Fertilisers are manufactured by using chemicals .they supply nitrogen phoshorus and potassium (NPK) . They are used for good vegetative growth (i.e., growth of leaves branches and flowers). Giving rise to healthy plants is commercially one of the major components for obtaining higher yields, especially in expensive farming practices.
Fertilisers contain much higher amount of nutrients in comparison to the manures and are therefore used in very small quantities . Chemically they may be inoroganic compounds. (e.g. ammonium sulphate) or organic compounds (e.g., urea). On the basis of the availability of nutrients from them fertilisers are divided into following four groups
(i) Nitrogenous fertilisers these fertilisers supply the macronutrient nitrogen.
Examples of nitrogenous fertilisers are Urea `(CO(NH_(2))_(2)),` ammonium nitrate `(NH_(4)NO_(3))`
(ii) Phosphatic fertilisers They are the source of the macronutrient phosphorus .
Examples of phosphatic fertilisers are dicalcium phosphate.
(iii) Potassic fertilisers These fertilisers supply potassium which is one of hte or potassium chloride (KCI) Potassium nitrate `(KNO_(3))`
(iv) Complex fertilisers When a fertiliser contains atleast two or more nutrients `(N,P_(2)O_(5) " and " K_(2)O)` it is called complex fertilisers.
Examples of complex fertilisers are
(i) Nitrophosphate
(ii) Ammonium phosphate
(iii) Urea ammonium phosphate