JNTU B.Pharmacy II PHARMACEUTICAL ORGANIC CHEMISTRY-II Previous Question Paper (December-2019 - R17)

Benzene consists of six carbon atoms arranged in a planar hexagonal ring. Each carbon atom is sp² hybridized, forming three sigma bonds: two with adjacent carbon atoms and one with a hydrogen atom, all lying in the same plane with bond angles of 120°.

The remaining unhybridized p-orbital on each carbon atom is perpendicular to the plane of the ring. These six parallel p-orbitals overlap laterally above and below the plane of the ring to form a continuous cloud of delocalized pi-electrons, which provides the molecule with its characteristic stability and aromatic character.

DDT stands for Dichlorodiphenyltrichloroethane. Its chemical structure consists of two chlorophenyl groups attached to a central carbon atom, which is also bonded to a trichloromethyl group. The chemical formula is C₁₄H₉Cl₅.

Its primary uses include:

• It was historically used as a powerful insecticide to control malaria, typhus, and other insect-borne diseases.
• It was widely applied in agriculture to protect crops from various pests.
• Due to its persistence in the environment and bioaccumulation, its use is now strictly regulated or banned in many countries, though it remains used in specific public health programs to control mosquito populations.