Organic Chemistry Practice Questions

Organic Chemistry Practice Questions

• Skraup synthesis is used to synthesize quinoline.
• Pyridine is more basic than aniline.
• Reaction of imidazole with HNO3/H2SO4 gives 4-nitroimidazole.
• Furan is the most aromatic heterocycle among furan, pyrrole, and thiophene.
• Electrophilic substitution in furan occurs at the 2nd position.
• Reaction of quinoline to 2-aminoquinoline uses NaNH2/liquid ammonia.
• The starting material for Paal-Knoor synthesis of furan is a 1,4-diketo compound.

Aromaticity

• The correct order of aromaticity is Thiophene > Pyrrole > Furan.
• Pyridine-3-carboxylic acid is the product of the given reaction.
• 2,3-dihydropyrrole is non-aromatic in nature.

Amino Acids and Polymers

• Tyrosine is the phenolic group-containing amino acid.
• Syndiotactic polymers are propylene polymers in which methyl groups have alternate positions along the chain.
• Thermoplastics are soft and viscous when heated.

Nucleic Acids and Steroids

• Isobutyryl group is used to protect cytosine.
• Steroidal ester hydrolysis exhibits the following order of reactivity: equatorial groups are hydrolyzed faster than axial groups.
• The steroid core in cortisone is pregnane.
• Bromination of 5a-cholestan-3-one yields a 3-bromo derivative.
• Catalytic hydrogenation of steroidal ketones under neutral conditions gives a trans-di equatorial diol.

Other Practice Questions (Cosmetics and Pharmaceuticals)

• Acacia is a polysaccharide emulsifying agent.
• The ratio of oil:water:gum for mineral oil emulsion is 3:2:1.
• The pH range for Pseudomonas aeruginosa contamination is 6-8.
• Schedule M(II) in the D and C Act lists cosmetic products.
• Oral pharmaceutical suspensions are thermodynamically unstable.
• The dispersed phase in a biphasic liquid is the internal phase.
• Emulsifier with HLB 12 promotes the formation of oil-in-water (o/w) emulsions.
• The dosage form for rectal administration is a suppository.
• Drug penetration through skin can be altered by factors including decreasing the resistance of the stratum corneum, changing its hydration and structure of lipids.
• Factors affecting systemic absorption of drug following rectal administration include pKa of drug, lipid-water partition coefficient, and colonic & gastrointestinal pH.
• Cocoa butter, gelatin, and polyethylene glycol are commonly used suppository bases.
• Objectives of sensorial testing include interpreting consumer responses and assessing product acceptance, as well as checking for safety.
• Hydrofluoroalkanes are commonly used propellants in aerosols.
• Diagnostic, prophetic, and photopatch tests are used in sensitivity testing of cosmetics.
• Quality control tests for aerosols include disintegration, melting point, discharge rate, and dissolution.
• Semisolids are evaluated for properties like pH, viscosity, spreadability, and crushing strength.

Pharmaceutical Biotechnology

• The stir in an airlift fermenter is done using mechanical stirrer.
• Equipment sterilization, media preparation, recovery, and purification are part of the downstream process.
• Oral polio vaccine (Sabin) is a live vaccine.
• BCG is used for protection against tuberculosis.
• Restriction enzymes are called molecular scissors.
• Type II restriction enzymes are used in recombinant DNA experiments.
• Ligase enzyme joins foreign genes in a vector.
• Plasmids are obtained from bacteria.
• Cosmids are obtained from bacteria and viruses.
• Post-translational modifications are absent in bacteria.
• The first step in PCR is denaturation.
• Enzyme immobilization is an eco-friendly process.